Officers said the altercation, which took place around 01:45 on Sunday in the area of Bean Around the World on Burrard Street, potentially involved as many as four men.
They described one of the men as being seriously injured, and said that a 29-year-old was subsequently arrested.
Pictured: The fight, Police said, took place outside Bean Around the World.
The “grave and criminal assault” suspect has since been released on bail pending further enquiries.
Police say they would now like to speak to anyone who saw what happened or knows more – particularly two male members of the public who intervened and spoke to the Police shortly afterwards.
Anyone with information is asked to contact 612612 or make an anonymous online report via Crimestoppers.