- Statement of Changes in Beneficial Ownership (4)

FORM 4 [ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5
	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(f) of the Investment Company Act of 1940

1. Name and Address of Reporting Person ^* WALSH PETER	2. Issuer Name and Ticker or Trading Symbol AMERISTAR CASINOS INC [ ASCA ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __ X __ Officer (give title below) _____ Other (specify below) SVP, GC, Chief Admin Officer
(Last) (First) (Middle) 16633 VENTURA BOULEVARD, SUITE 1050	3. Date of Earliest Transaction (MM/DD/YYYY) 12/14/2011
(Street) ENCINO, CA 91436 (City) (State) (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _ X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	12/14/2011		M		6500	A	$13.18	45147	I	Family Trust ⁽¹⁾
Common Stock	12/14/2011		S		5400	D	$17.15	39747	I	Family Trust ⁽¹⁾
Common Stock	12/14/2011		S		300	D	$17.1534	39447	I	Family Trust ⁽¹⁾
Common Stock	12/14/2011		S		100	D	$17.16	39347	I	Family Trust ⁽¹⁾
Common Stock	12/14/2011		S		600	D	$17.17	38747	I	Family Trust ⁽¹⁾
Common Stock	12/14/2011		S		100	D	$17.215	38647	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		M		10718	A	$13.18	49365	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		3124	D	$17.15	46241	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		2096	D	$17.1519	44145	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		676	D	$17.1559	43469	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		600	D	$17.1588	42869	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		300	D	$17.16	42569	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		200	D	$17.1663	42369	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		300	D	$17.17	42069	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		300	D	$17.1733	41769	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		400	D	$17.18	41369	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		100	D	$17.19	41269	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		200	D	$17.195	41069	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		500	D	$17.2	40569	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		400	D	$17.21	40169	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		200	D	$17.22	39969	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		300	D	$17.23	39669	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		522	D	$17.24	39147	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		400	D	$17.25	38747	I	Family Trust ⁽¹⁾
Common Stock	12/15/2011		S		100	D	$17.26	38647	I	Family Trust ⁽¹⁾
Common Stock								84890 ⁽²⁾	D

*Table II - Derivative Securities Beneficially Owned ( e.g.* , puts, calls, warrants, options, convertible securities)**
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)			11. Nature of Indirect Beneficial Ownership (Instr. 4)
Employee Stock Option (Right to Buy)	$13.18	12/14/2011		M			6500	4/2/2003 ⁽³⁾	3/8/2012	Common Stock	6500	$ 0	103500	I	Family Trust ⁽¹⁾
Employee Stock Option (Right to Buy)	$13.18	12/15/2011		M			10718	4/2/2003 ⁽³⁾	3/8/2012	Common Stock	10718	$ 0	92782	I	Family Trust ⁽¹⁾

Explanation of Responses:
( 1)	Securities owned by the Walsh Family Trust dated 9-11-03, of which Mr. Walsh and his spouse are co-trustees.
( 2)	Balance includes previously reported restricted stock units and performance share units, each of which constitutes the right to receive one share of common stock in the future.
( 3)	Option vested in five equal annual installments commencing on April 2, 2003.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
WALSH PETER 16633 VENTURA BOULEVARD SUITE 1050 ENCINO, CA 91436			SVP, GC, Chief Admin Officer

Signatures
/s/ Peter C. Walsh		12/16/2011
^** Signature of Reporting Person		Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
*	If the form is filed by more than one reporting person, see Instruction 4(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).
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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