Mark Connor was last seen around 3.35pm on December 15, in the Cairnhill Circus area of the Southside.
He is described as 6ft 1in tall, with a shaven head and a brown beard.
At the time of his disappearance, he was wearing grey jogging bottoms, a black and green Xbox Christmas jumper, an orange light padded jacket, and a navy bobble hat with a yellow stripe.
Cops believe Mark may be travelling in a black MG ZS with the registration SL22 DVB.
Police are now appealing to the public to come forward with any information on Mark’s whereabouts.
Inspector Graeme Smith, of Govan Police Office, said: “We are extremely concerned for Mark’s welfare and are urgently trying to trace him to ensure he’s safe and well.
“I would urge anyone with information regarding his whereabouts, or the vehicle, to contact Police Scotland on 101 quoting incident number 2194 of December 15.
“Mark, if you see this appeal, please make contact with police so we can make sure you’re okay.”
Anyone with information that could help the investigation is urged to contact Police Scotland on 101.
