Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-89486) pertaining to the Questar Corporation Employee Investment Plan of our report dated June 22, 2010, with respect to the financial statements and schedules of the Questar Corporation Employee Investment Plan included in this Annual Report (Form 11-K) for the year ended December 31, 2009.

/s/ Ernst & Young LLP

Salt Lake City, Utah

June 22, 2010