The Vernon Hills Police Department said they were called to the 900-block of South Milwaukee Avenue at about 10:43 p.m.
She was struck in the northbound lanes of the roadway, police said.
First responders tried to save the victim, but she died at the scene, police said.
The driver of vehicle remained at the scene and is cooperating with the investigation, police said. Impairment is not suspected in the crash at this time, police said.
Police said the that section of Milwaukee is a four-lane, lighted roadway with no designated pedestrian crossings.
The Major Crash Assistance Team of Lake County is assisting the Vernon Hill Police Department in the investigation.