Officials say, just before 1:30 a.m. Friday, a Kia Niro was traveling southbound on the northbound lanes of Route 1 and collided with a tractor-trailer head-on, just south of U.S. 40.
Delaware State Police say the impact sent the vehicle flying into the air. The car then landed on a guardrail. Police say the 29-year-old driver was not wearing a seat belt and was ejected from the vehicle. He was pronounced dead at the scene.
The driver of the tractor-trailer was not injured.
Route 1 was closed in both directions for almost six hours. The road has since reopened.
The crash remains under investigation.