At around 4:00 p.m. Sunday, authorities say, a motorcyclist rear ended a car in the northbound lanes.
The motorcyclist was rushed to Christiana Hospital for treatment.
Delaware State Police have confirmed that there is one fatality, but has not given further information.
The crash caused northbound I-495 to be temporarily shut down to allow police to conduct their investigation.
Officials are trying to determine if the speed of the motorcyclist was a contributing factor in the crash.