UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number      811-21579     

NUVEEN FLOATING RATE INCOME OPPORTUNITY FUND

(Exact name of registrant as specified in charter)

     333 West Wacker Drive, Chicago, Illinois 60606     
(Address of principal executive offices) (Zip code)

Kevin J. McCarthy—Vice President and Secretary
     333 West Wacker Drive, Chicago, Illinois 60606     
(Name and address of agent for service)

Registrant’s telephone number, including area code:      312-917-7700     

Date of fiscal year end:        7/31      

Date of reporting period:    4/30/2011   

Form N-Q is to be used by management investment companies, other than small business investment companies registered on Form N-5 (§§ 239.24 and 274.5 of this chapter), to file reports with the Commission, not later than 60 days after the close of the first and third fiscal quarters, pursuant to rule 30b1-5 under the Investment Company Act of 1940 (17 CFR 270.30b1-5). The Commission may use the information provided on Form N-Q in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-Q, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-Q unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to the Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

 

 

Item 1. Schedule of Investments

		Portfolio of Investments
		Nuveen Floating Rate Income Opportunity Fund (JRO) April 30, 2011 (Unaudited)

						Weighted
Principal						Average
Amount (000)				Description (1)		Coupon				Maturity (2)				Ratings (3)				Value
				Variable Rate Senior Loan Interests – 114.9% (84.8% of Total Investments) (4)
				Aerospace & Defense – 2.0% (1.5% of Total Investments)
$	574			DAE Aviation Holdings, Inc., Term Loan B1			5.280	%			7/31/14				B			$	580,931
	553			DAE Aviation Holdings, Inc., Term Loan B2			5.280	%			7/31/14				B				559,631
	281			Hawker Beechcraft, LLC, LC Facility			2.307	%			3/26/14			CCC+					248,477
	477			Hawker Beechcraft, LLC, Term Loan B			10.500	%			3/26/14			CCC+					486,397
	4,550			Hawker Beechcraft, LLC, Term Loan			2.238	%			3/26/14			CCC+					4,018,214
	1,486			Transdigm, Inc., Term Loan			4.000	%			6/30/17			Ba2					1,503,857
	7,921			Total Aerospace & Defense															7,397,507
				Airlines – 1.4% (1.0% of Total Investments)
	2,000			Delta Air Lines, Inc., Revolving Loan, Delayed Draw			0.750	%			3/28/13			Ba2					(68,125	)
	5,166			United Air Lines, Inc., Term Loan B			2.313	%			2/01/14			BB-					5,049,270
	7,166			Total Airlines															4,981,145
				Auto Components – 3.3% (2.5% of Total Investments)
	8,356			Federal-Mogul Corporation, Tranche B, Term Loan			2.173	%			12/29/14			Ba3					8,164,403
	4,264			Federal-Mogul Corporation, Tranche C, Term Loan			2.151	%			12/28/15			Ba3					4,166,330
	12,620			Total Auto Components															12,330,733
				Biotechnology – 1.6% (1.2% of Total Investments)
	3,600			Grifols, Term Loan, WI/DD			0.000	%			11/01/16			BB					3,639,917
	2,500			Onex Carestream Finance LP, Term Loan			5.000	%			2/25/17			Ba2					2,346,562
	6,100			Total Biotechnology															5,986,479
				Building Products – 3.2% (2.4% of Total Investments)
	3,000			Goodman Global Inc., Second Lien Term Loan			9.000	%			10/28/17				B-				3,113,751
	8,623			Goodman Global Inc., Term Loan			5.750	%			10/28/16				B+				8,712,232
	11,623			Total Building Products															11,825,983
				Capital Markets – 0.3% (0.2% of Total Investments)
	295			BNY Convergex Group LLC, Incremental Term Loan			5.250	%			12/19/16				B+				297,530
	703			BNY Convergex Group LLC, Term Loan			5.250	%			12/19/16				B+				709,072
	998			Total Capital Markets															1,006,602
				Chemicals – 3.1% (2.3% of Total Investments)
	1,438			Hexion Specialty Chemicals, Inc., Tranche C, Term Loan B1			4.000	%			5/05/15			Ba3					1,432,655
	608			Hexion Specialty Chemicals, Inc., Tranche C, Term Loan B2			4.063	%			5/05/15			Ba3					605,774
	1,362			Ineos US Finance LLC, Tranche B2			7.500	%			12/16/13				B1				1,412,469
	1,363			Ineos US Finance LLC, Tranche C2			8.000	%			12/16/14				B1				1,413,336
	2,145			Styron S.a.r.l. Corporation,Term Loan			6.000	%			8/02/17				B+				2,169,413
	4,239			Univar, Inc., Term Loan			5.000	%			6/30/17				B				4,276,847
	11,155			Total Chemicals															11,310,494
				Commercial Banks – 0.3% (0.2% of Total Investments)
	1,197			Fifth Third Processing Solutions LLC, Term Loan			5.500	%			11/03/16			BB-					1,209,419
				Commercial Services & Supplies – 0.3% (0.2% of Total Investments)
	88			ServiceMaster Company, Delayed Term Loan			2.720	%			7/24/14				B+				86,994
	886			ServiceMaster Company, Term Loan			2.763	%			7/24/14				B+				873,565
	974			Total Commercial Services & Supplies															960,559
				Communications Equipment – 4.9% (3.6% of Total Investments)
	5,081			Avaya, Inc., Term Loan B3			4.811	%			10/26/17				B1				4,929,728
	7,205			Avaya, Inc., Term Loan			3.061	%			10/27/14				B1				7,059,044
	5,200			Intelsat, Term Loan			5.250	%			4/02/18			BB-					5,258,094
	973			Telcordia Technologies, Inc., New Term Loan			6.750	%			4/30/16				B+				976,104
	18,459			Total Communications Equipment															18,222,970
				Diversified Consumer Services – 2.7% (2.0% of Total Investments)
	3,990			Advantage Sales and Marketing, Inc., Term Loan, First Lien			5.250	%			12/17/17				B+				4,015,751
	1,796			Brickman Group Holdings, Inc., Tranche B, Term Loan			7.250	%			10/14/16				B+				1,835,150
	2,131			Cengage Learning Acquisitions, Inc., Term Loan			2.460	%			7/03/14				B+				2,055,366
	252			Laureate Education, Inc., Delayed Draw Term Loan			3.524	%			8/15/14				B1				250,269
	1,681			Laureate Education, Inc., Term Loan B			3.524	%			8/15/14				B1				1,671,512
	9,850			Total Diversified Consumer Services															9,828,048
				Diversified Financial Services – 2.7% (2.0% of Total Investments)
	1,243			CIT Group, Inc., Tranche 3, Term Loan			6.250	%			8/11/15			BB					1,263,875
	1,723			FoxCo Acquisition Sub LLC, Term Loan			4.768	%			7/14/15				B+				1,731,143
	500			Nexeo Solutions LLC, Term Loan			5.000	%			2/16/17				B1				503,334
	6,594			Pinafore LLC, Term Loan			4.250	%			9/29/16			BB					6,664,689
	10,060			Total Diversified Financial Services															10,163,041
				Diversified Telecommunication Services – 2.3% (1.7% of Total Investments)
	2,000			Intelsat, Unsecured Term Loan			2.776	%			2/01/14				B				1,961,562
	4,533			Level 3 Financing, Inc., Term Loan			2.533	%			3/13/14				B+				4,474,894
	157			MetroPCS Wireless, Inc., Tranche B1, Term Loan			4.071	%			11/03/13			Ba1					157,737
	1,987			WideOpenWest Finance LLC, Term Loan, First Lien			2.721	%			6/30/14				B1				1,924,515
	8,677			Total Diversified Telecommunication Services															8,518,708
				Electric Utilities – 0.5% (0.3% of Total Investments)
	2,022			TXU Corporation, 2014 Term Loan			3.736	%			10/10/14				B2				1,747,834
				Electronic Equipment & Instruments – 0.5% (0.4% of Total Investments)
	2,000			NDS Group, Ltd., Term Loan			4.000	%			3/12/18			Ba2					2,008,750
				Food & Staples Retailing – 2.4% (1.8% of Total Investments)
	9,144			U.S. Foodservice, Inc., Term Loan			2.710	%			7/03/14				B2				8,866,077
				Food Products – 2.3% (1.7% of Total Investments)
	192			Darling International, Inc., Term Loan			5.000	%			12/17/16			BBB-					193,680
	1,000			Great Atlantic and Pacific Tea Company, Inc., Term Loan			8.750	%			6/14/12			BB-					1,016,225
	2,756			Michael Foods Group, Inc., Term Loan			4.250	%			2/25/18				B+				2,783,401
	2,985			Pierre Foods, Inc., Term Loan			7.000	%			9/30/16				B+				3,011,740
	1,332			Pinnacle Foods Finance LLC, Tranche D, Term Loan			6.000	%			4/02/14			Ba3					1,349,646
	8,265			Total Food Products															8,354,692
				Health Care Equipment & Supplies – 0.9% (0.7% of Total Investments)
	235			Fenwal, Inc., Delayed Term Loan			2.561	%			2/28/14				B				222,152
	747			Fenwal, Inc., Term Loan			2.561	%			2/28/14				B				705,108
	1,217			Symbion, Inc., Term Loan A			3.461	%			8/23/13				B1				1,180,005
	1,382			Symbion, Inc., Term Loan B			3.461	%			8/25/14				B1				1,340,055
	3,581			Total Health Care Equipment & Supplies															3,447,320
				Health Care Providers & Services – 11.5% (8.5% of Total Investments)
	3,000			Emergency Medical Services, Term Loan, WI/DD			5.250	%			4/27/18				B+				3,022,125
	1,728			Gentiva Health Services, Inc., Term Loan B			4.750	%			8/17/16			Ba2					1,749,727
	9,000			Golden Living, Term Loan, WI/DD			5.000	%			4/28/18				B1				8,850,942
	1,133			Healthspring, Term Loan			6.000	%			10/21/16			Ba3					1,136,260
	2,279			IASIS Healthcare LLC, PIK Term Loan			5.554	%			6/16/14			CCC+					2,302,833
	2,750			Kindred Healthcare, Term Loan, WI/DD			6.500	%			3/28/18			Ba3					2,745,704
	501			LifeCare, Term Loan			8.063	%			2/01/16			Ba2					507,333
	1,885			MultiPlan, Inc., Term Loan B			4.750	%			8/26/17			Ba3					1,896,865
	3,750			National Mentor Holdings, Inc., Tranche B			7.000	%			2/09/17				B+				3,712,500
	898			Renal Advantage, Inc., Tranche B, Term Loan			5.750	%			12/17/16			Ba3					908,692
	3,482			Skilled Healthcare Group, Inc., Term Loan			5.250	%			4/09/16				B+				3,475,158
	1,486			Sun Healthcare Group, Inc., Term Loan			7.500	%			10/18/16			Ba2					1,488,080
	6,444			Universal Health Services, Inc., Term Loan B			4.000	%			11/15/16			BB+					6,487,313
	4,384			Vanguard Health Holding Company II LLC, Initial Term Loan			5.000	%			1/29/16			Ba2					4,406,162
	42,720			Total Health Care Providers & Services															42,689,694
				Hotels, Restaurants & Leisure – 8.9% (6.6% of Total Investments)
	2,978			24 Hour Fitness Worldwide, Inc., New Term Loan			6.750	%			4/22/16			Ba3					2,973,132
	500			Ameristar Casinos, Inc., Term Loan B			4.000	%			4/16/18			BB+					505,223
	1,895			Burger King Corporation, Tranche B			4.500	%			10/19/16			BB-					1,896,598
	1,400			Caesars Octavius LLC, Term Loan, WI/DD			9.250	%			4/25/17				B				1,404,364
	97			CBRL Group, Inc., Term Loan B2			1.820	%			4/26/13			BB-					96,626
	1,599			CCM Merger, Inc., Term Loan			7.000	%			3/01/17				B+				1,622,624
	1,500			Harrah’s Operating Company, Inc., Term Loan B1			3.274	%			1/28/15				B				1,409,475
	2,000			Harrah’s Operating Company, Inc., Term Loan B2			3.255	%			1/28/15				B				1,878,334
	1,975			Harrah’s Operating Company, Inc., Term Loan B3			3.274	%			1/28/15				B				1,855,722
	3,092			Orbitz Worldwide, Inc., Term Loan			3.253	%			7/25/14				B+				2,944,844
	308			OSI Restaurant Partners LLC, Revolver			0.099	%			6/14/13				B+				302,484
	2,804			OSI Restaurant Partners LLC, Term Loan			2.500	%			6/14/14				B+				2,755,217
	1,016			Reynolds Group Holdings, Inc., US Term Loan			4.250	%			2/09/18			BB					1,022,815
	1,919			Seaworld Parks and Entertainment, Inc., Term Loan B			4.000	%			8/17/17			BB+					1,935,420
	2,742			Shingle Springs Tribal Gaming Authority, Term Loan			10.500	%			12/17/13			BB					2,618,214
	2,200			Six Flags Theme Parks, Inc., Tranche B, Term Loan			5.250	%			6/30/16			BB					2,221,542
	1,925			Travelport LLC, Delayed Term Loan			4.744	%			8/21/15			Ba3					1,889,357
	827			Venetian Casino Resort LLC, Delayed Term Loan			3.000	%			11/23/16			BB-					815,451
	2,814			Venetian Casino Resort LLC, Tranche B, Term Loan			3.000	%			11/23/16			BB-					2,770,891
	33,591			Total Hotels, Restaurants & Leisure															32,918,333
				Household Products – 3.3% (2.4% of Total Investments)
	5,188			Spectrum Brands, Inc., Term Loan			5.010	%			6/17/16				B2				5,254,756
	6,983			Visant Corporation, Term Loan			5.250	%			12/22/16			BB-					7,025,233
	12,171			Total Household Products															12,279,989
				Industrial Conglomerates – 0.6% (0.4% of Total Investments)
	995			Evertec, Inc., Term Loan			5.500	%			9/30/16			BB-					1,002,462
	1,067			Presidio, Inc., Term Loan			7.250	%			3/31/17			Ba3					1,069,334
	2,062			Total Industrial Conglomerates															2,071,796
				Internet Software & Services – 1.9% (1.4% of Total Investments)
	756			Open Solutions, Inc., Term Loan B			2.395	%			1/23/14			BB-					677,892
	3,810			Sabre, Inc., Term Loan			2.229	%			9/30/14				B1				3,527,824
	2,935			SkillSoft Corporation, Term Loan			6.500	%			5/26/17			BB					2,986,524
	7,501			Total Internet Software & Services															7,192,240
				IT Services – 8.0% (5.9% of Total Investments)
	800			Attachmate Corporation, Second Lien Term Loan, WI/DD			9.500	%			10/27/17			CCC+					799,000
	3,000			Attachmate Corporation, Term Loan			6.500	%			4/27/17			BB-					3,007,500
	8,453			First Data Corporation, Extended Term Loan			4.213	%			3/24/18				B+				8,033,745
	814			First Data Corporation, Term Loan B2			2.963	%			9/24/14				B+				774,499
	86			First Data Corporation, Term Loan B3			2.963	%			9/24/14				B+				81,464
	122			Infor Global Solutions Intermediate Holdings, Ltd., Delayed Term Loan			3.970	%			7/28/12				B+				121,039
	533			Infor Global Solutions Intermediate Holdings, Ltd., Extended Delayed Draw Term Loan			5.970	%			7/28/15				B+				522,727
	5,934			Infor Global Solutions Intermediate Holdings, Ltd., Holdco PIK Term Loan			8.200	%			9/02/14				N/R				4,934,825
	2,658			Infor Global Solutions Intermediate Holdings, Ltd., Second Lien Delayed Draw, DD1			6.461	%			3/02/14			CCC+					2,432,375
	1,015			Infor Global Solutions Intermediate Holdings, Ltd., Term Loan			5.970	%			7/28/15				B+				1,009,829
	259			Infor Global Solutions Intermediate Holdings, Ltd., Term Loan, First Lien			3.970	%			7/28/12				B+				256,803
	4,592			Infor Global Solutions Intermediate Holdings, Ltd., Term Loan, Second Lien, DD1			6.461	%			3/02/14			CCC+					4,222,901
	2,015			SunGard Data Systems, Inc., Term Loan B			1.979	%			2/28/14			BB					1,999,487
	1,496			Syniverse Holdings, Inc., Term Loan			5.250	%			12/21/17			BB-					1,513,394
	31,777			Total IT Services															29,709,588
				Leisure Equipment & Products – 2.9% (2.1% of Total Investments)
	2,042			BLB Management Services, Inc., Term Loan			8.500	%			11/05/15			BB-					2,058,160
	7,579			Bombardier Recreational Products, Inc., Term Loan			2.786	%			6/28/13				B-				7,530,356
	1,169			Cedar Fair LP, Term Loan			4.000	%			12/15/17			Ba2					1,181,313
	10,790			Total Leisure Equipment & Products															10,769,829
				Media – 9.6% (7.1% of Total Investments)
	1,500			Charter Communications Operating Holdings LLC, Holdco Term Loan			2.711	%			3/06/14			BB+					1,483,594
	768			Cumulus Media, Inc., Term Loan			3.461	%			6/11/14				B-				763,305
	1,177			Gray Television, Inc., Term Loan B			3.750	%			12/31/14				B				1,171,713
	1,500			HIT Entertainment, Inc., Term Loan			5.820	%			2/26/13			CCC-					1,392,500
	2,898			HIT Entertainment, Inc., Term Loan B			5.561	%			6/01/12				B2				2,872,918
	2,837			Interactive Data Corporation, Term Loan B			4.750	%			2/11/18			Ba3					2,859,613
	694			Miramax Film, LLC, Term Loan			7.750	%			7/01/16			Ba2					702,519
	82			Nielsen Finance LLC, Term Loan A			2.231	%			8/09/13			Ba2					81,414
	2,948			Spanish Broadcasting System, Inc., Term Loan B			2.060	%			6/11/12				B-				2,876,824
	1,703			SuperMedia, Term Loan			11.000	%			12/31/15				B-				1,148,769
	12,057			Tribune Company, Term Loan B, (5)			0.000	%			6/04/14			Ca					8,418,439
	10,758			Univision Communications, Inc., Term Loan			4.461	%			3/31/17				B				10,540,616
	3,190			Yell Group PLC, Term Loan			3.961	%			7/31/14				N/R				1,288,752
	42,112			Total Media															35,600,976
				Metals & Mining – 2.0% (1.5% of Total Investments)
	2,000			Fairmount Minerals, Ltd., Tranche B, Term Loan			5.250	%			3/15/17			BB-					2,013,438
	3,990			Novelis, Inc., Term Loan			4.000	%			3/10/17			BB-					4,036,136
	1,500			Walter Energy, Term Loan			4.000	%			4/02/18			BB-					1,514,907
	7,490			Total Metals & Mining															7,564,481
				Multiline Retail – 0.7% (0.5% of Total Investments)
	2,695			Neiman Marcus Group, Inc., Term Loan			4.310	%			4/06/16			BB-					2,703,548
				Oil, Gas & Consumable Fuels – 2.6% (1.9% of Total Investments)
	498			Alon USA Energy, Inc., Edgington Facility			2.561	%			8/05/13				B+				443,535
	3,987			Alon USA Energy, Inc., Paramount Facility			2.527	%			8/05/13				B+				3,548,154
	1,684			Big West Oil LLC, Term Loan			7.000	%			3/31/16				B2				1,709,474
	2,917			CCS Income Trust, Term Loan			3.242	%			11/14/14				B				2,793,839
	1,133			Western Refining, Inc., Term Loan			7.500	%			3/15/17				B				1,150,029
	10,219			Total Oil, Gas & Consumable Fuels															9,645,031
				Paper & Forest Products – 2.4% (1.8% of Total Investments)
	3,766			Newark Group, Inc., DIP Term Loan			12.500	%			3/31/14				N/R				3,897,743
	5,107			Wilton Products, Term Loan			3.570	%			8/01/14				N/R				4,902,247
	8,873			Total Paper & Forest Products															8,799,990
				Personal Products – 1.0% (0.8% of Total Investments)
	3,733			NBTY, Inc., Term Loan B1			4.250	%			10/01/17			BB-					3,764,076
				Pharmaceuticals – 2.0% (1.5% of Total Investments)
	2,234			ConvaTec Healthcare, Term Loan			5.750	%			12/30/16			Ba3					2,245,921
	1,995			Edwards Limited New Term Loan, First Lien			5.500	%			5/31/16				B+				2,002,481
	3,125			Graceway Pharmaceuticals LLC, Second Lien Term Loan, (5)			4.941	%			5/03/13			Ca					177,084
	1,894			Graceway Pharmaceuticals LLC, Term Loan, (5)			4.961	%			5/03/12			Caa2					1,145,638
	860			Warner Chilcott Corporation, Term Loan B1			4.250	%			3/17/18			BBB-					868,537
	430			Warner Chilcott Corporation, Term Loan B2			4.250	%			3/17/18			BBB-					434,269
	592			Warner Chilcott Corporation, Term Loan B3			4.250	%			3/17/18			BBB-					597,119
	11,130			Total Pharmaceuticals															7,471,049
				Real Estate Investment Trust – 2.1% (1.5% of Total Investments)
	7,624			iStar Financial, Inc., Tranche A1			5.000	%			6/28/13				B1				7,579,815
				Real Estate Management & Development – 4.8% (3.5% of Total Investments)
	8,937			Capital Automotive LP, Tranche B			5.000	%			3/11/17			Ba3					8,914,508
	3,500			LNR Property Corporation, Term Loan, WI/DD			4.750	%			4/26/16			Ba2					3,526,250
	5,457			Realogy Corporation, Delayed Term Loan			4.562	%			10/10/16				B1				5,138,792
	17,894			Total Real Estate Management & Development															17,579,550
				Road & Rail – 2.5% (1.8% of Total Investments)
	518			Avis Budget Car Rental LLC, Term Loan			5.750	%			4/19/14			Ba1					520,499
	8,431			Swift Transportation Company, Inc., Term Loan			6.000	%			12/21/16			BB-					8,538,370
	8,949			Total Road & Rail															9,058,869
				Semiconductors & Equipment – 2.0% (1.5% of Total Investments)
	1,189			Freescale Semiconductor, Inc., Term Loan			4.493	%			12/01/16				B1				1,190,746
	5,000			NXP Semiconductor LLC, Term Loan			4.500	%			3/04/17				B-				5,059,375
	1,113			Spansion LLC, Term Loan			6.250	%			2/09/15			BB-					1,122,543
	7,302			Total Semiconductors & Equipment															7,372,664
				Software – 2.1% (1.5% of Total Investments)
	2,096			Dealer Computer Services, Inc., Term Loan			3.750	%			4/21/18			BB+					2,116,247
	2,000			IPC Systems, Inc., Term Loan, Second Lien			5.557	%			6/01/15			CCC					1,955,000
	3,720			IPC Systems, Inc., Term Loan			2.517	%			6/02/14				B1				3,673,984
	7,816			Total Software															7,745,231
				Specialty Retail – 4.3% (3.2% of Total Investments)
	3,741			Burlington Coat Factory Warehouse Corporation, Term Loan B			6.250	%			2/23/17				B-				3,741,665
	825			Claire’s Stores, Inc., Term Loan B			3.051	%			5/29/14				B				783,495
	2,000			J Crew Group, Term Loan			4.750	%			3/07/18				B1				1,998,922
	3,667			Jo-Ann Stores, Inc., Term Loan			4.750	%			3/16/18				B+				3,671,250
	2,098			Michaels Stores, Inc., Term Loan B1			2.584	%			10/31/13				B+				2,082,978
	3,587			Toys “R” Us — Delaware, Inc., Term Loan			6.000	%			9/01/16			BB-					3,620,006
	15,918			Total Specialty Retail															15,898,316
				Wireless Telecommunication Services – 5.0% (3.7% of Total Investments)
	4,844			Asurion Corporation, Term Loan			3.248	%			7/03/14				B+				4,831,127
	13,564			Clear Channel Communications, Inc., Tranche B, Term Loan			3.861	%			11/13/15			CCC+					12,108,488
	1,714			MetroPCS Wireless, Inc., Tranche B2, Term Loan			4.071	%			11/03/16			Ba1					1,724,279
	20,122			Total Wireless Telecommunication Services															18,663,894
$	444,301			Total Variable Rate Senior Loan Interests (cost $415,017,287)															425,245,320
Shares				Description (1)														Value
				Common Stocks – 3.3% (2.4% of Total Investments)
				Building Products – 1.3% (0.9% of Total Investments)
	124,402			Masonite Worldwide Holdings, (6), (7)														$	4,727,276
				Hotels, Restaurants & Leisure – 0.1% (0.1% of Total Investments)
	42,041			BLB Worldwide Holdings Inc., (7)															441,431
				Media – 1.9% (1.4% of Total Investments)
	33,696			Citadel Broadcasting Corp Class B Shares, (6)															1,149,034
	7,400			Citadel Broadcasting Corporation, (6)															252,266
	193,006			Metro-Goldwyn-Mayer, (7)															4,358,712
	600			Philadelphia Newspapers LLC, (7)															61,200
	33,776			Readers Digest Association Inc., (6), (7)															1,106,164
				Total Media															6,927,376
				Total Common Stocks (cost $18,892,222)															12,096,083

Principal
Amount (000)				Description (1)		Coupon				Maturity				Ratings (3)				Value
				Convertible Bonds – 0.5% (0.3% of Total Investments)
				Communications Equipment – 0.5% (0.3% of Total Investments)
$	1,000			Nortel Networks Corporation, (5)			1.750	%			4/15/12				N/R			$	870,000
	1,000			Nortel Networks Corporation, (5)			2.125	%			4/15/14				D				870,000
	2,000			Total Communications Equipment															1,740,000
$	2,000			Total Convertible Bonds (cost $1,698,255)															1,740,000

Principal
Amount (000)				Description (1)		Coupon				Maturity				Ratings (3)				Value
				Corporate Bonds – 8.6% (6.4% of Total Investments)
				Construction Materials – 0.3% (0.2% of Total Investments)
$	1,000			Headwaters Inc., 144A			7.625	%			4/01/19				B+			$	1,017,500
				Diversified Telecommunication Services – 0.2% (0.2% of Total Investments)
	1,000			Nortel Networks Limited, (5)			0.000	%			7/15/11				N/R				880,000
				Health Care Equipment & Supplies – 0.7% (0.6% of Total Investments)
	2,500			Merge Healthcare Inc.			11.750	%			5/01/15				B+				2,700,000
				Health Care Providers & Services – 1.4% (1.0% of Total Investments)
	2,000			Aurora Diagnostics Holdings LLC, 144A			10.750	%			1/15/18				B3				2,060,000
	1,000			LifeCare Holdings Inc.			9.250	%			8/15/13			Caa3					720,000
	2,500			Select Medical Corporation			6.211	%			9/15/15			CCC+					2,443,750
	5,500			Total Health Care Providers & Services															5,223,750
				IT Services – 1.4% (1.1% of Total Investments)
	4,000			First Data Corporation, 144A			7.375	%			6/15/19				B+				4,075,000
	1,167			First Data Corporation			10.550	%			9/24/15				B-				1,219,246
	5,167			Total IT Services															5,294,246
				Machinery – 0.6% (0.4% of Total Investments)
	2,000			NES Rental Holdings Inc., 144A			12.250	%			4/15/15			CCC+					2,002,500
				Media – 1.7% (1.2% of Total Investments)
	3,750			Clear Channel Communications, Inc.			10.750	%			8/01/16			CCC-					3,646,874
	3,600			Clear Channel Communications, Inc.			6.875	%			6/15/18			CCC-					2,601,000
	7,350			Total Media															6,247,874
				Multiline Retail – 0.7% (0.5% of Total Investments)
	2,250			Sprectum Brands Inc., 144A			9.500	%			6/15/18				B1				2,514,375
				Oil, Gas & Consumable Fuels – 0.4% (0.3% of Total Investments)
	1,400			Western Refining Inc., 144A			10.750	%			6/15/14				B				1,512,000
				Paper & Forest Products – 0.1% (0.1% of Total Investments)
	500			Catalyst Paper Co.			7.375	%			3/1/14			Caa2					347,500
				Road & Rail – 0.5% (0.4% of Total Investments)
	2,000			Avis Budget Car Rental			2.813	%			5/15/14				B				1,945,000
				Wireless Telecommunication Services – 0.6% (0.4% of Total Investments)
	2,000			Sprint Nextel Corporation			8.375	%			8/15/17			BB-					2,242,500
$	32,667			Total Corporate Bonds (cost $29,311,940)															31,927,245
Shares				Description (1)														Value
				Warrants – 0.9% (0.7% of Total Investments)
	100,096			Citadel Broadcasting Corporation														$	3,428,288
				Total Warrants (cost $3,050,426)															3,428,288

Principal
Amount (000)				Description (1)		Coupon				Maturity								Value
				Short-Term Investments – 7.3% (5.4% of Total Investments)
$	26,925			Repurchase Agreement with Fixed Income Clearing Corporation, dated 4/29/11, repurchase price $26,925,467, collateralized by $27,060,000 U.S. Treasury Notes, 1.125%, due 12/15/12, value $27,465,900			0.010	%			5/02/11							$	26,925,445
				Total Short-Term Investments (cost $26,925,445)															26,925,445
				Total Investments (cost $494,895,575) – 135.5%															501,362,381
				Borrowings — (31.7)% (8), (9)															(117,270,000	)
				Other Assets Less Liabilities — (3.8)%															(14,078,153	)
				Net Assets Applicable to Common Shares – 100%														$	370,014,228

Investments in Derivatives

Swaps outstanding at April 30, 2011:

Fund

Fixed Rate

Unrealized

Notional

Pay/Receive

Floating Rate

Fixed Rate

Payment

Effective

Termination

Appreciation

Counterparty

Amount

Floating Rate

Index

(Annualized)

Frequency

Date (10)

Date

(Depreciation)

Goldman Sachs

$

29,317,500

Receive

1-Month USD-LIBOR

1.300

%

Monthly

4/20/11

4/20/14

$

(102,645

)

Goldman Sachs

29,317,500

Receive

1-Month USD-LIBOR

0.344

Monthly

4/20/11

4/20/12

(8,664

)

Morgan Stanley

29,317,500

Receive

1-Month USD-LIBOR

2.201

Monthly

4/20/11

4/20/16

(183,037

)

$

(294,346

)

Fair Value Measurements

Fair value is defined as the price that the Fund would receive upon selling an investment or transferring a liability in an orderly transaction to an independent buyer in the principal or most advantageous market of the investment. A three-tier hierarchy is used to maximize the use of observable market data and minimize the use of unobservable inputs and to establish classification of fair value measurements for disclosure purposes. Observable inputs reflect the assumptions market participants would use in pricing the asset or liability. Observable inputs are based on market data obtained from sources independent of the reporting entity. Unobservable inputs reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Unobservable inputs are based on the best information available in the circumstances. The three-tier hierarchy of inputs is summarized in the three broad levels listed below:

			Level 1 — Quoted prices in active markets for identical securities.
			Level 2 — Other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.).
			Level 3 — Significant unobservable inputs (including management’s assumptions in determining the fair value of investments).

The inputs or methodologies used for valuing securities are not an indication of the risk associated with investing in those securities. The following is a summary of the Fund’s fair value measurements as of April 30, 2011:

		Level 1				Level 2				Level 3				Total
Investments:
Variable Rate Senior Loan Interests		$	—			$	425,245,320			$	—			$	425,245,320
Common Stocks*			1,401,300				10,694,783				—				12,096,083
Convertible Bonds			—				1,740,000				—				1,740,000
Corporate Bonds			—				31,927,245				—				31,927,245
Warrants			3,428,288				—				—				3,428,288
Short-Term Investments			—				26,925,445				—				26,925,445
Derivatives:
Interest Rate Swaps**			—				(294,346	)			—				(294,346	)
Total		$	4,829,588			$	496,238,447			$	—			$	501,068,035

*  Refer to the Fund’s Portfolio of Investments for industry breakdown of Common Stocks classified as Level 2.

**  Represents net unrealized appreciation (depreciation).

During the period ended April 30, 2011, the Fund recognized no significant transfers to/from Level 1, Level 2 or Level 3.

Derivative Instruments and Hedging Activities

The Fund records derivative instruments at fair value, with changes in fair value recognized on the Statement of Operations, when applicable. Even though the Fund ’s investments in derivatives may represent economic hedges , they are not considered to be hedge transactions for financial reporting purposes.

The following table presents the fair value of all derivative instruments held by the Fund as of March 31, 2011, the location of these instruments on the Statement of Assets and Liabilities, and the primary underlying risk exposure.

Location on the Statement of Assets and Liabilities

Underlying

Derivative

Asset Derivatives

Liability Derivatives

Risk Exposure

Instrument

Location

Value

Location

Value

Interest Rate

Swaps

Unrealized appreciation on swaps*

$

—

Unirealized depreciation on swaps*

$

294,396

* Represents cumulative gross unrealized appreciation (depreciation) of swap contracts as reported in the Portfolios of Investments.

Income Tax Information

The following information is presented on an income tax basis. Differences between amounts for financial statement and federal income tax purposes are primarily due to the treatment of paydown gains and losses, timing differences in recognizing certain gains and losses on investment transactions and recognition of premium amortization. To the extent that differences arise that are permanent in nature, such amounts are reclassified within the capital accounts on the Statement of Assets and Liabilities presented in the annual report, based on their federal tax basis treatment; temporary differences do not require reclassification. Temporary and permanent differences do not impact the net asset value of the Fund.

At April 30, 2011, the cost of investments was $495,453,056.

Gross unrealized appreciation and gross unrealized depreciation of investments at April 30, 2011, were as follows:

				Gross unrealized:
				Appreciation		$	22,017,353
				Depreciation			(16,108,028	)
				Net unrealized appreciation (depreciation) of investments		$	5,909,325

			For Fund portfolio compliance purposes, the Fund’s industry classifications refer to any one or more of the industry sub-classifications used by one or more widely recognized market indexes or ratings group indexes, and/or as defined by Fund management. This definition may not apply for purposes of this report, which may combine industry sub-classifications into sectors for reporting ease.
	(1)		All percentages shown in the Portfolio of Investments are based on net assets applicable to Common shares unless otherwise noted.
	(2)		Senior Loans generally are subject to mandatory and/or optional prepayment. Because of these mandatory prepayment conditions and because there may be significant economic incentives for a Borrower to prepay, prepayments of Senior Loans may occur. As a result, the actual remaining maturity of Senior Loans held may be substantially less than the stated maturities shown.
	(3)		Ratings: Using the highest of Standard & Poor’s Group (“Standard & Poor’s”), Moody’s Investor Service, Inc. (“Moody’s”) or Fitch, Inc. (“Fitch”) rating. Ratings below BBB by Standard & Poor’s, Baa by Moody’s or BBB by Fitch are considered to be below investment grade. Holdings designated N/R are not rated by any of these national rating agencies.
	(4)		Senior Loans generally pay interest at rates which are periodically adjusted by reference to a base short-term, floating lending rate plus an assigned fixed rate. These floating lending rates are generally (i) the lending rate referenced by the London Inter-Bank Offered Rate (“LIBOR”), or (ii) the prime rate offered by one or more major United States banks.
			Senior Loans may be considered restricted in that the Fund ordinarily is contractually obligated to receive approval from the Agent Bank and/or Borrower prior to the disposition of a Senior Loan.
	(5)		At or subsequent to the end of the reporting period, this security is non-income producing. Non-income producing security, in the case of a bond, generally denotes that the issuer has (1) defaulted on the payment of principal or interest, (2) is under the protection of the Federal Bankruptcy Court or (3) the Fund’s Adviser has concluded that the issue is not likely to meet its future interest payment obligations and has directed the Fund’s custodian to cease accruing additional income on the Fund’s records.
	(6)		Non-income producing; issuer has not declared a dividend within the past twelve months.
	(7)		For fair value measurement disclosure purposes, Common Stock categorized as Level 2.
	(8)		Borrowings as a percentage of Total Investments is 23.3%.
	(9)		The Fund may pledge up to 100% of its eligible investments in the Portfolio of Investments as collateral for Borrowings.
	(10)		Effective date represents the date on which both the Fund and Counterparty commence interest payment accruals on each forward swap contract.
	N/R		Not rated.
	144A		Investment is exempt from registration under Rule 144A of the Securities Act of 1933, as amended. These investments may only be resold in transactions exempt from registration, which are normally those transactions with qualified institutional buyers.
	DD1		Investment or portion of investment purchased on a delayed delivery basis.
	WI/DD		Purchased on a when-issued or delayed delivery basis.
	USD-LIBOR		United States Dollar-London Inter-Bank Offered Rate.

Item 2. Controls and Procedures.

	a.		The registrant’s principal executive and principal financial officers, or persons performing similar functions, have concluded that the registrant’s disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the “1940 Act”) (17 CFR 270.30a-3(c))) are effective, as of a date within 90 days of the filing date of this report that includes the disclosure required by this paragraph, based on their evaluation of the controls and procedures required by Rule 30a-3(b) under the 1940 Act (17 CFR 270.30a-3(b)) and Rule 13a-15(b) or 15d-15(b) under the Securities Exchange Act of 1934 (17 CFR 240.13a-15(b) or 240.15d-15(b)).
	b.		There were no changes in the registrant’s internal control over financial reporting (as defined in Rule 30a-3(d) under the 1940 Act (17 CFR 270.30a-3(d)) that occurred during the registrant’s last fiscal quarter that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 3. Exhibits.

File as exhibits as part of this Form a separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the 1940 Act (17 CFR 270.30a-2(a)), exactly as set forth below: EX-99 CERT Attached hereto.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(Registrant) NUVEEN FLOATING RATE INCOME OPPORTUNITY FUND

Date June 29, 2011

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Date June 29, 2011

Date June 29, 2011