Elle Smith, aged 16, was reported missing from the Armthorpe area this morning.
She was last seen in Woodlea Grove at 1.30am.
Elle has long, wavy, light brown hair and was wearing a grey off-the-shoulder jumper, black jeans and black slip on shoes.
A South Yorkshire Police spokeswoman said: "We need your urgent help to find Elle Smith, who was reported missing from the Armthorpe area of Doncaster this morning."
Anyone with information should call 101.