A 23-year-old Afghan man has died at a Melbourne detention centre after his roommate found him on the floor.

It is understood emergency services were called to the Melbourne Immigration Transit Accommodation Centre in Broadmeadows about 11.30pm on Friday but the man was pronounced dead shortly after.

On Saturday morning, a Victoria Police spokesman confirmed the man's death and said it was not being treated as suspicious.

The man's roommate, who slept in the upper bunk, told The Age he was woken by a loud sound and found the deceased face down on the floor.

"I heard some bang, something dropped, like heavy," he said.