The accident happened at about 4:30 a.m between exits 61 and 62 of the LIE.
Suffolk County Police say 33-year old Matthew Polashek, of Ridgewood, Queens, was heading west when his car veered onto the right shoulder and struck a Dodge pickup truck that was parked there.
His wife, 30-year old Stacie Polashek, was pronounced dead at the scene.
Matthew was taken to Stony Brook Medical Center with non-life-threatening injuries.
The Dodge was disabled and unoccupied at the time.
Both vehicles have been impounded for safety checks.
All westbound lanes of the LIE were closed at Exit 62 and traffic was detoured to the service road while police investigated.
