Fourteen-year-old Naiha Shah was reported missing from her home in Hunslet at around 11.55am on Thursday and has not had any contact with her family since then.
She is described as being of mixed race and medium build, with brown hair tied up in a bun and she has a split lip.
She was last seen wearing an oversized Nike hoodie, dark blue jeans and pink trainers.
Detective Sergeant James Gross, of West Yorkshire Police, said: “We are increasingly concerned about Naiha’s welfare and are appealing to the public to come forward with any information to her whereabouts to help with our enquiries.
“Anyone with any information is asked to contact the police via 101 quoting log number 496 of 11 August.”