Ownership Submission
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
OMB APPROVAL
OMB Number: 3235-0104
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
  Tarrant Veronica
 2. Date of Event Requiring Statement (Month/Day/Year)
05/10/2005		 3. Issuer Name and Ticker or Trading Symbol
POWER ONE INC [PWER]
(Last)
(First)
(Middle)
740 CALLE PLANO		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP, Fin.& Chief Acctg. Officer
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

CAMARILLO, CA 93012		 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 8,332
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

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
Employee Stock Option 1528-10/1/01 10/01/2002(1) 10/01/2011 Common Stock 11,000 $ 5.77 D  
Employee Stock Option 2408-1/8/03 01/08/2004(2) 01/08/2013 Common Stock 11,000 $ 6.02 D  
Employee Stock Option 2456-1/17/03 01/17/2004(3) 01/17/2013 Common Stock 4,000 $ 5.9 D  
Employee Stock Option 2661-7/21/04 02/23/2005(4) 07/21/2014 Common Stock 30,000 $ 9.12 D  
Employee Stock Option 966-6/29/00 06/29/2001(5) 06/29/2010 Common Stock 30,000 $ 51.97 D  
NQSO (Contingent Expiration) 10/01/2004(6) 10/01/2011 Common Stock 15,000 $ 5.77 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Tarrant Veronica
740 CALLE PLANO
CAMARILLO, CA 93012		       VP, Fin.& Chief Acctg. Officer  

Signatures

By: Randall H. Holliday, Attorney-in-Fact for 05/18/2005
**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) For the noted grant, dated 10/1/01, 25% of the shares vest on each of the first, second, and third anniversaries of the date of grant, and 25% vest on 2/23/05, at which time all shares will be fully vested and exercisable.
(2) For the noted grant, dated 1/8/03, 25% of shares vest on the first anniversary of the date of grant, 25% on the second anniversary of the date of grant, and 50% on 2/23/05.
(3) For the noted grant, dated 1/17/03, 25% of shares vest on the first anniversary of the date of grant, 25% on the second anniversary of the date of grant, and 50% on 2/23/05.
(4) All shares fully vest on 2/23/05.
(5) For the noted grant, dated 6/29/00, 25% of the shares vest on each anniversary of the date of grant, until the fourth anniversary of the date of grant, at which time all shares will be fully vested and exercisable.
(6) For the noted grant, the option expires on the earlier to occur of (a) six months plus one day following the Trigger Date (as defined in the grant agreement), or (b) tenth anniversary of the date of grant. The shortened period for exercise associated with alternative (a) may occur at any time once a Trigger Date has occurred, even if same occurs after vesting of the option.

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

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.