Richard Wheat, 52, entered the guilty plea to a count of wire fraud before U.S. District Judge James Ware on Monday.
He will be sentenced by Ware on Sept. 29. The charge carries a theoretical maximum penalty of 20 years in prison, but the judge will consider federal sentencing guidelines before setting the penalty.
Wheat was chief financial officer of the facility, also known as George L. Mee Memorial Hospital, in King City from 1999 until he was fired in January 2004.
U.S. Attorney Joseph Russoniello said Wheat admitted during the guilty plea to using his position to set up automatic electronic payment from the hospital's bank account to his personal bank account beginning in 2002.
Russoniello said Wheat admitted the hospital paid for at least $30,000 of his personal expenses for travel, hotels, entertainment, restaurants, home office supplies, automobile parts and gas.
The single wire fraud count was related to a 2003 wire transfer of funds from the hospital's bank account to Wheat's personal account.
Wheat's defense attorney was not immediately available for comment.