Police are looking for a man and woman after a late-night assault inside a busy Braddon bar on Lonsdale Street.

Security CCTV suggests that at about 2.20am on December 7, a man allegedly assaulted another man inside the premises before fleeing the venue.

Police say the man was accompanied by a woman, who left the venue shortly after the incident.

The man is described as Caucasian in appearance with short hair. He was wearing a dark-coloured shirt that ripped during the incident, long pants and Nike-branded sneakers. Police allege he removed his shirt and ran north along Lonsdale Street after the assault.

The woman was wearing a white T-shirt and black leggings.

Anyone who witnessed the incident or can help identify either person should contact the police via the Crime Stoppers website or by calling 1800 333000.