The crash happened around 7:30 a.m. Wednesday as the driver, a 64-year-old woman from Darby Township, was traveling southbound on Route 1 toward Middletown.
Police say she lost control of the vehicle just before the Ridley Creek Bridge. The van crossed over a lane of traffic slammed into an embankment.
The van then flipped onto its side and the victim, who was not wearing a seatbelt, was thrown and rescuers found her pinned under the vehicle.
She was pronounced dead at the scene.
Officials are not yet releasing her name pending notification of family.
No other vehicles were involved and no other injuries were reported.