Ownership Submission
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

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 *
HOLBROOK CONNIE C
  2. Issuer Name and Ticker or Trading Symbol
QUESTAR CORP [STR]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Sr. VP, Gen. Counsel, Corp Sec
(Last)
(First)
(Middle)
180 EAST 100 SOUTH
3. Date of Earliest Transaction (Month/Day/Year)
03/23/2005
(Street)

SALT LAKE CITY, UT 84111
4. If Amendment, Date Original Filed(Month/Day/Year)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction 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)
Code V Amount (A) or (D) Price
Common Stock and attached Common Stock Purchase Rights 03/23/2005   M   150 A $ 15 148,876 D  
Common Stock and attached Common Stock Purchase Rights 03/23/2005   M   3,100 A $ 22.95 151,976 D  
Common Stock and attached Common Stock Purchase Rights 03/23/2005   F   1,930 D $ 57.68 150,046 (1) D  
Common Stock and attached Common Stock Purchase Rights               30,317.313 (2) I Employee Investment Plan

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction 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
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(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)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock and attached Common Stock Purchase Rights $ 15 03/23/2005   M     150 08/08/2000 02/08/2010 Common Stock and attached Common Stock Purchase Rights 150 $ 15 90,069 D  
Common Stock and attached Common Stock Purchase Rights $ 22.95 03/23/2005   M     3,100 08/11/2002 02/11/2012 Common Stock and attached Common Stock Purchase Rights 3,100 $ 22.95 86,969 D  
Phantom Stock Units $ 0               (3)   (3) Phantom Stock Units 0   8,381.6652 (4) D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
HOLBROOK CONNIE C
180 EAST 100 SOUTH
SALT LAKE CITY, UT 84111
      Sr. VP, Gen. Counsel, Corp Sec  

Signatures

 Connie C. Holbrook   03/24/2005
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) I exercised an option to purchase 3,100 shares of stock using 1,225 shares as consideration. I satisfied my tax withholding obligation by selling 705 shares to Questar.
(2) As of March 23, 2005, I had 30,317.3130 equivalent shares of stock in my account in the Employee Investment Plan. The number of equivalent shares will fluctuate as Questar's stock price changes, this fluctuation does not reflect any transactions that should be reported.
(3) This date has not been filled in since I am not reporting any changes in my phantom stock units.
(4) I receive phantom stock units as a result of my participation in an excess benefit plan. This total includes 3,521.2162 units in such plan in addition to units held through my account balance in deferred compensation plans. This total also reflects a March 22nd allocation to such excess benefit plan.

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