Elliott Henri Alexandre, 30, left his home in the Plateau neighbourhood of Montreal at around 2 a.m. on Sunday morning. He has not been seen since.
He is black, weighs about 265 pounds and is about 6'3".
His family says often spends time walking in Verdun, Lasalle and on the mountain.
Anyone with information about his whereabouts is encouraged to call Montreal police at 514-393-1133.