Police received a call around 7 p.m. about a collision between two people in the house on Aylwin Street, near the intersection of Hochelaga and Sherbrooke streets.
The woman in her 20s was stabbed at least once in the upper part of her body. He was taken to hospital in critical condition.
The suspect, a 32-year-old man, was arrested near the spot with blood on him, according to information from CTV.
After his arrest, he was taken to a detention center to meet with investigators.
The man was known to the police before the fight.
Police told CTV News they were trying to determine if and how the two knew each other.
Police have set up a perimeter that allows investigators to investigate the scene.
