Gurdip Kang, 49, of Shaggy Calf Lane, was reported missing yesterday morning (Saturday) after he left his home address without informing any of his family about where he was going.
Gurdip is described as wearing a black turban, a navy fleece jacket, with a white polo shirt and black trousers.
Acting Det Insp Tim Rose said: "Gurdip's family are growing increasingly concerned for his welfare as not only was it out of character for him to leave the house without informing anyone about where he was going, but he has now been missing for three days.
"Inquiries are on-going to try and find Gurdip, however we would urge anyone with information of his whereabouts to come forward and speak to us immediately."
Anyone with information should contact Thames Valley Police via the 24-hour Thames Valley Police Enquiry Line on 101, quoting URN 626 (5/5).