The crash happened at about 2:00 a.m. Friday on Bear Corbitt Road (Route 7) approaching Lower Twin Lane Road in the city of Bear.
Police say the 2006 Ford F-150 pickup truck was traveling at a high rate of speed when it crossed the center line into the southbound lanes, across traffic and off the road.
The front of the truck slammed into a concrete bridge abutment, then rolled down the embankment, coming to rest on its roof in a ditch.
Rescue workers had to pry open the smashed cabin to free the driver. The 47-year-old man, identified as Robert J. Kettner of Middletown, Del., was taken to Christiana Hospital where he later died from his injuries.
The preliminary investigation determined that the driver was the sole occupant of the truck and was properly restrained.
Police are continuing to investigate.