Police say alcohol was a factor in this crash.
It happened on Lancaster Pike near Newport Gap Pike around 2:10 a.m. Friday.
Police say the driver, 20-year-old Candace Carhart, of Wilmington, lost control of the car and it flipped.
A male passenger, 30-year-old Stephen Herbster, who was not wearing a seatbelt, was ejected from the vehicle.
Herbster was pronounced dead at Christiana Hospital.
Carhart suffered non life-threatening injuries. Police say she was wearing a seatbelt.
No charges has been filed as of yet.