At around 9.45pm on Tuesday, January 26, 2021, officers were called to a report of an assault near to Marks and Spencer on Mosley Street, close to Piccadilly Gardens.
A man in his 30s was kicked to the head and left unconscious on floor.
He was seriously injured and taken to hospital for treatment and discharged.
Detective Constable Mel Brundrit, from GMP's City of Manchester division, said: "This was a nasty assault on a man in the city centre which left him with serious head injuries.
"We've carried out a number of lines of enquiry but now we're asking the public to come forward if they recognise the man pictured."
Anyone with any information should call 0161 856 4409, quoting incident number 2662 of 26/01/2021.
Alternatively, contact Crimestoppers anonymously on 0800 555 111.
