State police say it happened just before 3 a.m. Friday on Interstate 495 at Terminal Avenue in the New Castle area.
According to investigators, the driver - a 20-year-old Wilmington man - was traveling in the southbound center lane when someone in an unknown vehicle opened fire from his right lane.
Multiple gunshots were fired, police say, and the driver was hit once in a lower extremity.
The victim exited I-495 and made it to the area of Route 141 on I-295 before his car broke down.
The man was then transported to the hospital for non-life-threatening injuries.
Police say, so far, there is no description of the suspect's vehicle.
Our 6abc data journalism team found statistics on highway shootings. The Gun Violence Archive shows highway shootings are up 57% nationally from 540 in 2019 to 846 in 2021.
Drivers say they notice a shift in behavior on the roads.
"It's like the Wild West, but with cars instead of horses," said Mike Battersby of Ridley Park.
Anyone with information is asked to contact Delaware state police at 302-365-8446.