State troopers responded to the scene, at the intersection of SE Highpoint Way and SE 79th Street, at about 8:35 a.m. after receiving a report of a serious crash.
The driver of the car was found dead at the scene. There were no passengers.
A preliminary investigation found that the man was heading west on I-90 about four miles east of Issaquah in a 2001 Toyota Celica when the car veered off the freeway to the right, the State Patrol reported.
The Toyota rolled and crashed at the nearby intersection in its top.
The name of the driver was withheld pending notification of his next of kin.