Faith McLellan was last seen near Buchanan Bus Station in the city at around 9.30pm on Saturday, January 27.
The 16-year-old from Greenock is described as being 6ft 1 inch tall and has long dark hair with orange sections at the front.
She was last seen wearing green trousers, a black Tommy Hilfiger jacket, and white and black Jordan shoes.
Anyone with information on the teens whereabouts is asked to contact police on 101 quoting incident number 3296 of January 29.
