Police say the victim was approached by a man in the Botanic Court area off the Ormeau Road who demanded his wallet at knife point.
The suspect is described as small with ginger hair and in his early twenties, wearing grey tracksuit bottoms and a hat.
Investigating officer Detective Sergeant McCambridge said: “It was reported that at approximately 9.15pm on Tuesday 21st February, a male was approached by a male in the Botanic Court area of Belfast.
“The male who was described as being small with ginger hair and in his early twenties, wearing grey tracksuit bottoms and a hat approached the male and demanded his wallet at knife point.
“The male then made off in the direction of Carmel Street in the Belfast area.
“We are appealing to anyone that may have any information or to anyone that may have witnessed any suspicious activity in the area at the time to contact detectives at Musgrave Reactive and Organised Crime Branch on the non-emergency number 101, quoting reference 1262 of the 21/02/17.
“Or, alternatively if someone would prefer to provide information without giving their details they can contact the independent charity Crimestoppers and speak to them anonymously on 0800 555 111.”