The 13-year-old was 'struck over the head' on Thursday afternoon.
West Yorkshire Police say a schoolgirl has been attacked by a man in Lightcliffe.
Officers were called at around 3.30pm on Thursday to a report a 13-year-old girl had been assaulted on a snicket off Stoney Lane.
She was walking in the direction of Aysgarth Avenue when the man approached her and is reported to have struck her on the head.
The victim managed to run onto Aysgarth Avenue where she approached a member of the public and asked for assistance.
Detective Inspector Gary Stephenson said: “Our enquiries are ongoing to trace the male involved and I would appeal for anyone with information to contact police.
“We will have extra officers patrolling the area today to provide reassurance to the community and conducting house to house and CCTV enquiries.
“I would appeal for anyone who saw a male acting suspiciously in the area at around the time of the assault or anyone with information to contact police.”