Police said Jim McCormick, 44, from Scotstoun, was last seen at around 1:20 am on Tuesday while walking along Dumbarton Road, Glasgow, between Crow Road and Hayburn Street.
He is described as white and 6ft 2ins tall. He has a slim build, short brown hair and brown eyes.
When last seen, he was wearing a dark blue, waterproof jacket with reflective horizontal lines on the back, black cycle leggings with reflective patches on the calf, and black cycle shoes with silver clips.
Inspector Duncan Evans at Drumchapel Police Office said: “Mr McCormick’s family are becoming increasingly concerned that they haven’t heard from him and urge him to get in contact to let them know he is safe and well.
“Due to the fact he was wearing cycling shoes, someone may remember seeing him walking rather awkwardly and his shoes clicking as he walked.
“Anyone who has seen him since the early hours of this morning, Tuesday, 6 February, or anyone who knows of his present whereabouts is asked to contact police at Drumchapel immediately via 101 quoting incident number 1426 of 5 February 2018.”