Police were called to a licensed venue on George Street in Croydon at 12:10am on Wednesday (January 1).
The scene was attended by police and ambulance crews from London Ambulance Service.
A man was taken to hospital where his injuries were later assessed as non-life changing.
An investigation has been opened by Metropolitan Police, however no arrests have currently been made.
A spokesperson for Metropolitan Police said: “Police were called to George Street, Croydon, at 00:10hrs on Wednesday, 1 January, after a man was reportedly stabbed inside a licensed venue.
“The London Ambulance Service attended alongside officers. The victim was taken to hospital, where his injuries were assessed to be non-life changing.
“At this early stage of the investigation, there have been no arrests.”
A London Ambulance Service spokesperson said: “We were called at 12,08am on Wednesday 1 January to reports of a stabbing incident in George Street, Croydon.
“We sent resources to the scene, including ambulance crews, a paramedic in a fast response car, an incident response officer and London’s Air Ambulance.
“The first of our crews arrived in four minutes.
“Our crews treated a man at the scene, before taking him to hospital by road.”
