Longueuil police are looking for 15-year-old Vincent Dilaj, who was last seen on June 23 in Boucherville.
His family is worried for his safety as he was involved with suspicious adults.
Dilaj is a blue-eyed boy with brown hair, who weighs 82 kilograms and measures 6 feet tall.
Police say they have reason to believe he may be in downtown Montreal or around the South Shore.
Anyone with information is urged to call 911.