Police say they are concerned for the welfare of 38-year-old Gareth Silverstone, who has been missing since Saturday afternoon.
Mr Silverstone, from Kidwelly, was last seen in Carmarthen. Police say he is approximately 6ft tall with a slim build and brown hair.
He is known to have links to Carmarthen, Llangain and Pembrokeshire. Anybody with more information is asked to call 101.