Lake County Sheriff's Police said the crash occurred around 3 a.m. in the 16000 block of west Illinois Route 173, in Wadsworth.
When officials arrives, they found a red 2002 Chevrolet Blazer on its side off the roadway, and the 45-year-old man unresponsive.
Paramedics from the Newport Township Fire Protection District determined he was dead at the scene.
Investigators say the car was traveling eastbound on Route 173 approaching North Mill Creek Road, when for an unknown reason, it entered the westbound lanes of traffic, and went into the embankment on the north side of the roadway.
The car then struck a utility pole and trees before coming to a stop on its side, officials said.
Crash investigators and the Lake County Coroner’s Office are working to determine if impairment was a factor in this crash. The identification of the driver is being withheld pending notification to his family, police said.
The investigation will continue through the Sheriff’s Technical Crash Investigations Team.