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 *   Kirloskar Virendra A 2. Date of Event Requiring Statement (Month/Day/Year) 03/31/2008 3. Issuer Name and Ticker or Trading Symbol KLA TENCOR CORP [KLAC] (Last) (First) (Middle) C/O KLA-TENCOR CORPORATION, 160 RIO ROBLES 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Accounting Officer 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) SAN JOSE, CA 95134 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ 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) Common Stock 274 D   Common Stock - Restricted Stock Units 20,100 D Â

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
Non-Qualified Stock Option (right to buy)	05/21/2004(1)	05/21/2013	Common Stock	2,500 (3)	$ 39.35	D	Â
Non-Qualified Stock Option (right to buy)	10/27/2004(1)	10/27/2013	Common Stock	3,200	$ 53.86	D	Â
Non-Qualified Stock Option (right to buy)	10/27/2004(1)	01/27/2014	Common Stock	1,600	$ 58.1	D	Â
Non-Qualified Stock Option (right to buy)	10/27/2004(1)	04/26/2014	Common Stock	1,267 (4)	$ 45.16	D	Â
Non-Qualified Stock Option (right to buy)	10/27/2004(1)	08/02/2014	Common Stock	760 (5)	$ 40.66	D	Â
Non-Qualified Stock Option (right to buy)	11/16/2005(2)	09/16/2014	Common Stock	6,067 (6)	$ 39.89	D	Â
Non-Qualified Stock Option (right to buy)	09/16/2006(1)	09/16/2014	Common Stock	4,117 (7)	$ 39.89	D	Â
Non-Qualified Stock Option (right to buy)	09/26/2006(1)	09/26/2012	Common Stock	10,000	$ 47.95	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Kirloskar Virendra A C/O KLA-TENCOR CORPORATION 160 RIO ROBLES SAN JOSE, CA 95134	Â	Â	  Chief Accounting Officer	Â

Signatures

/s/ Virendra A. Kirloskar		04/04/2008
**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).
(1)	Twenty percent (20%) of the shares subject to this option became exercisable on this date, and the remaining shares became (or will become) exercisable in equal monthly installments over the subsequent 48 months.
(2)	One share subject to this option became exercisable on this date, and the remaining shares became (or will become) exercisable in equal monthly installments over the subsequent 46 months.
(3)	An option to purchase 15,000 shares was originally granted. As of the date hereof, 12,500 shares have been exercised.
(4)	An option to purchase 2,000 shares was originally granted. As of the date hereof, 733 shares have been exercised.
(5)	An option to purchase 1,200 shares was originally granted. As of the date hereof, 440 shares have been exercised.
(6)	An option to purchase 9,967 shares was originally granted. As of the date hereof, 3,900 shares have been exercised.
(7)	An option to purchase 6,500 shares was originally granted. As of the date hereof, 2,383 shares have been exercised.

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