The alarm was raised after members of the public came across the victim lying in Gardner’s Crescent at around 11.40pm on Thursday, 24 January.
He was taken to Edinburgh Royal Infirmary where he was treated for facial injuries before later being released.
Police believe he was attacked by a man sometime earlier that evening and inquiries are ongoing to trace him.
He is described as white and in his mid to late twenties, wearing a light-coloured t-shirt, grey jogging bottoms and carrying a blue carrier bag.
Constable Craig Moran from Wester Hailes Police Station said: “The victim sustained a number of facial injuries during this assault and our inquiries are ongoing to identify the culprit.
“Anyone who remembers seeing any suspicious activity within Gardners Crescent, or around the Fountainbridge area during the late evening of Thursday 24th January, should contact police immediately.
“In addition, anyone who can help us trace the man responsible should also come forward.”
Those with information can contact Wester Hailes Police Station via 101 and quote incident number 4189 of the 24th January. Alternatively, an anonymous report can be made to the charity Crimestoppers on 0800 555 111.
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