It accident happened in the 2000 block of South Broad Street around 4:30 Thursday afternoon.
Police say the 12-year-old girl was standing between two parked cars in the median when she walked into the northbound lane of traffic and was struck.
In the video, from a local shop on South Broad Street, a light-colored minivan can be seen flying by and a little girl is thrown onto the ground.
A second car also struck the little girl but remained on scene.
Within seconds, a crowd of on-lookers rushed to the young victim's side, stunned that the driver who allegedly caused the accident had sped off.
Robert Williams is a manager at Popeye's Restaurant on Broad Street near Snyder Avenue. He was inside the building, when his co-worker heard the child's screams.
"Heard the noise of a girl's scream. She flipped in the air and fell and was there when she fell," said Williams.
Police believe the striking vehicle may have been a light-colored, older-model Pontiac caravan. The car also has a missing passenger side mirror.
Authorities are hoping the surveillance video will help them catch the driver.
Meanwhile the young victim - who suffered broken legs and head injuries - is in stable condition at the Children's Hospital of Pennsylvania.
Anyone with information on the vehicle or the driver is asked to contact Philadelphia Police.