The crash happened at Hook and Calcon Hook roads in Darby Township around 3:30 p.m. Saturday.
Police say the woman lost control of her car and hit a utility pole.
The impact sent live wires on to her vehicle.
Rescuers had to wait until the power was shut off before cutting the woman from the car.
She was air-lifted to the Hospital of the University of Pennsylvania in critical condition.
Her name has not been released.