Police said 49-year-old Ricky Howard has been missing since Friday morning.
Officials said he was last seen at his home on Norway Road.
Howard is 6 feet tall, weighs 158 pounds and has blue eyes and brown/gray hair.
Authorities said he is believed to be wearing a black sweatshirt, black sweatpants with work boots.
They said he may have been operating his black 2008 Toyota RAV4 with Maine license plate number 5422 WQ.
Police are asking anyone who may have seen Howard in the Harrison or Waterford areas to please call the Oxford County Sheriff's Office at 743-9554.