Annette Merar, 65, was reported missing Friday, the Los Angeles Police Department told the Riverside (Calif.) Press-Enterprise.
Merar was described as a diabetic, who is 5 feet 2 inches tall and 160 pounds.
Her family told police she may appear confused, the newspaper said.
Spector is currently serving a sentence of 19 years to life in prison for a second-degree murder conviction in the 2003 shooting death of actress Lana Clarkson at his home. Spector married his fourth wife, Rachelle Short, in 2006.
The Press-Enterprise did not say when or for how long Merar was married to Spector.