Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the registration statement (No. 333-144132) on Form S-8 of FNB United Corp. of our report dated June 16, 2010, appearing in this Annual Report on Form 11-K of the FNB Retirement/Savings Plus Benefit Plan for the year ended December 31, 2009.

Charlotte, North Carolina

June 16, 2010

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