One man was sent to hospital in critical condition after a fight broke out in the Cosmopolitan Hotel in the area of Yonge and Colborne streets early Saturday.
Police were called to the scene just before 1 a.m. for reports of a fight.
A man in his 20s is was stabbed several times in the back. He is expected to be released from hospital later on Saturday.
Two others are being treated for minor injuries.
Police said two groups of people who appeared to be hotel guests were socializing when a verbal altercation broke out which led to a physical fight.
Police have not identified a motive for the assault.
The suspects are believe to be males, aged 18 to 22.
CORRECTION: An earlier version of this story said 3 people had been stabbed in a street robbery. The article has been updated to reflect the latest information from police.