Danika-Dior Hill, who lives in the Litherland area, was last seen at New Brighton train station getting on a train heading towards Liverpool Central station at just before 5.10pm yesterday, Tuesday, August 5.
She is described a white female, 5ft 5in tall, of slim build, with long dark brown hair.
When last seen she was wearing dark grey leggings, a light grey tracksuit sweatshirt and white and grey trainers.
She is also known to frequent the London area.
A spokesperson for Merseyside Police said: “If you see Danika-Dior please call 999 so we can make sure she’s safe. You can also pass on any sightings via our form: Add something to a missing person report | Merseyside Police any other information to @MerPolCC or 101.”