Paige Devine was last seen in the Ryelands area of Lancaster at around 7.30pm yesterday (February 19).
Police said they are growing concerned for the 14-year-old's welfare and are seeking the public's help to find her.
She is white, around 5ft 5 inches tall, of a slim build with long brown hair tied up.
She is believed to be wearing a purple and green coat, black leggings and pair of black and white checkered Vans trainers.
If you see Paige or know of her whereabouts, you can contact Lancashire Police on 101, quoting reference LC-20200219-1543.