The Southern Illinois 100 (formerly the Rust-Oleum Automotive Finishes 100) is an ARCA Menards Series stock car race held annually on the DuQuoin State Fairgrounds Racetrack during the DuQuoin State Fair on Labor Day weekend.
It is one of two dirt races on the ARCA schedule, the other being the Springfield ARCA 100 at the Illinois State Fairgrounds Racetrack, both of which are longtime events on the series schedule.
It has been a part of a national stock car circuit annually since 1954.
In the 2000s and 2010s, the race saw participation from NASCAR Cup Series regulars Tony Stewart and Ken Schrader.
Starting in 2022, ARCA would offer a $20,000 bonus if a driver were to win this race and the other dirt race at the Illinois State Fairgrounds Racetrack.