The crash happened around 11:30 p.m. at Comly and Tacony streets.
Medics arrived to find a man, approximately 50 years old, down on the roadway.
He was rushed to the hospital for treatment of severe head injuries.
Police say the striking driver was travelling northbound on Tacony and saw the pedestrian step in front of his car.
The driver said he tried to swerve, but the pedestrian again moved into the path of his vehicle.
Police say there are no charges in this incident.