Leo Ibbotson, 12, has special educational needs and received a phone call from the pair, who asked if he wanted to meet them to play a field on Farm Road, Kendray, in January.
However when he arrived, one of the girls pushed Leo onto the floor and attacked him, while the other girl filmed the incident on her phone.
Leo’s mum, 36-year-old Terrie Ibbotson, eventually received the recording and sent it to South Yorkshire Police, who yesterday confirmed they are carrying out enquiries.
Terrie told the Chronicle: “I went to the police straight away when I showed them the footage, the woman who dealt with the complaint said it was really distressing and she couldn’t watch it to the end.
“Leo has special educational needs and now suffers with his mental health on top of that, as a result of what happened to him.
“I am genuinely disgusted with the police’s handling of it I have been given five different crime numbers and I haven’t got any further forward.
“We are in May now four months since the assault took place and Leo has suffered a lot, emotionally, physically and mentally.
“Justice needs to be served.”
A police spokesperson added: “Police are investigating a reported assault of a 12-year-old boy in Barnsley.
“It is reported that the child was assaulted on January in the Farm Road area.
“Enquiries are ongoing.”