Austin Lolos scored two touchdowns, including an 18-yard run around the right end and a 10-yard run off right tackle.
Cory Cochran caught a pass from Billy Richey for the final TD.
Illini saw two big runs from Austin Goheen, who had one carry for about 40 yards and another for around 30 yards.
Trevor Carpenter had an interception late in the game.
Roxana scored with 1.4 seconds left in the game.
“We played a pretty good game,” Coach Roger Kirby said. “Logan Baecht had some nice catch and runs and Dustin Walker recovered a fumble.”
Illini defeated Alton Gray 22-20 last week.