FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person *   Sun Life Assurance CO of Canada 2. Date of Event Requiring Statement (Month/Day/Year) 05/07/2010 3. Issuer Name and Ticker or Trading Symbol Kayne Anderson MLP Investment CO [KYN] (Last) (First) (Middle) 150 KING STREET WEST,  4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) TORONTO, A6 M5H 1J9 6. Individual or Joint/Group Filing(Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) 5.57% Mandatory Redeemable Preferred Shares due May 7, 2017 $ 15,000,000 D   5.57% Mandatory Redeemable Preferred Shares due May 7, 2017 $ 15,000,000 I See below

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Sun Life Assurance CO of Canada 150 KING STREET WEST TORONTO, A6 M5H 1J9	Â	  X	Â	Â
SUN LIFE FINANCIAL INC SUN LIFE ASSURANCE CO OF CANADA 150 KING STREET WEST SUITE 1400 TORONTO, A6Â	Â	  X	Â	Â

Signatures

/s/ John T. Donnelly, Senior Managing Director - Investment Products and Strategies on behalf of Sun Life Assurance Company of Canada		05/18/2010
**Signature of Reporting Person		Date
/s/ Ann King, Assistant Vice President on behalf of Sun Life Assurance Company of Canada		05/18/2010
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
  Remarks: Sun Life Financial Inc. owns 100% of the outstanding shares of stock of Sun Life Assurance Company of Canada, the direct owner of the 5.57% Mandatory Redeemable Preferred Shares due May 7, 2017 of Kayne Anderson MLP Investment Company.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

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