Richard John Walsh, aged 57, of Blaengarw, Bridgend, was reported as missing on March 19 and concern is growing for his welfare.
On April 10, Mr Walsh was seen in Bute Park, Cardiff.
CCTV stills from the Post Office, Queen Street, Cardiff, on April 15, show him wearing a black jacket with a navy hoody underneath, a green army shirt, grey faded combat trousers, black boots and a green camouflage baseball cap. Mr Walsh was also said to be wearing a skull ring on his right hand and had a number of hoop earrings in his left ear. He is described as being 5ft2, of medium build, having a thick white beard and long grey hair.
Anyone with any information on his whereabouts is urged to call 101 quoting reference 1900097888.
Richard is also urged to get in contact to confirm he is safe and well.