At about 8:16 p.m. Friday, Joliet police officers responded to the area of Caton Farm Road and River Bend Lane for a report of a traffic crash.
According to preliminary information, a Mitsubishi Outlander driven by a 55-year-old Plainfield man was westbound on Caton Farm Road.
The vehicle left the roadway to the north and struck a tree near the entrance of the Lakewood on Caton Farm subdivision, police said.
The man was transported to an area hospital, where he was pronounced dead.
Police believe he may have suffered a medical event prior to the crash.
The crash is still under investigation.