Gerrard Burrell-Hodgson, 53, left his home on Deighton Lane, Deighton, North Yorkshire at 10am on Monday. He has not been seen since.
Mr Burrel-Hodgson is described as 6ft 1ins tall, with a stubble beard and short dark hair.
He is believed to be driving a grey Land Rover and could be in the Northallerton or Thirsk area.
North Yorkshire Police say they are extremely concerned for his welfare.
Anyone with information is urged to contact police on 101 or 999 for an immediate sighting.