Katie Davis, 18, was last seen on Saturday at 5 p.m. in the area of Bamburgh Circle in Toronto, according to police.
She is described as a Vietnamese female who is approximately five feet four inches tall and weighs 100 pounds with short black hair.
She was last seen wearing a black Blue Jays baseball hat, a bright pink hoody-style sweater with the words “Old Navy” on the front, grey pants and multi-coloured running shoes with orange laces.
Police say they are concerned for Davis' safety.
Anyone with information is asked to call 42 Division at 416-808-4200 or CrimeStoppers.