Franconia Township police officers were trying to stop the suspect's car when it swerved off the road and hit a fire hydrant before coming to a rest.
The driver, reported to be the only person inside, was seriously injured and had to be airlifted to Hahnemann University Hospital in Philadelphia.
The crash happened near Main Street and Harleysville Pike in Lower Salford Township, shortly before two o'clock Saturday morning.
Police have not said why they were pursuing the driver. His name has not been released.