Elizabeth T. Mather, of Kennett Square, was last seen in her car travelling south on Route 41 from Route 10 in West Fallowfield Township around 3:30 a.m. on Wednesday.
Mather is described as being around 5'2" tall, 125 pounds with gray-brown hair and blue eyes.
She was driving her green 2002 Volvo station wagon with PA plates RC2-G93.
Anyone with information is urged to call police at (610) 268-2022.