The woman had just returned to Highland Park from Chicago on a Metra train when the attack occurred.
Eduardo Franco, 20, of the 500 block of Ravinia Road, was charged with aggravated criminal sexual assault and robbery, the release said. He was arrested about 3 a.m. Saturday and his bond was set at $1 million.
Since the attack, police have increased patrols along the bike and jogging patch.
Franco will appear in court for a preliminary hearing a 10 a.m. on August 10.
