Metra officials said Train #52, scheduled to arrive at Ogilvie Transportation Center at 3:53 p.m., struck a vehicle near Kilbourn Avenue in Oak Park.
The driver is alive, Metra said. No additional details on the driver's condition were provided.
Trains were stopped in the area during the evening rush hour as officials inspected the tracks for damage.
Commuters should check the Metra website for the latest on service delays.