Illinois Route 102 is a state route in northeast Illinois. It runs from Illinois Route 53 in Wilmington to the concurrency of U.S. Route 45 and U.S. Route 52 in Bourbonnais, just north of Kankakee. This is a distance of 18.33 miles (29.50 km).

Illinois 102 runs parallel to and north of the Kankakee River for its entire length. For 2 miles (4 km), Illinois 102 is located next to the Kankakee River State Park. Entrances to the park's two major campgrounds are located off Illinois 102.

Illinois Route 113 takes a mostly parallel route, but on the south side of the river.

The road is two lanes for its entire length, except for a four-lane stretch with center turn lanes measuring approximately 1.5 miles (2.5 km) near its eastern terminus in Bourbonnais. A center turn lane also exists within a two-lane section for a few blocks inside the city of Wilmington.

Illinois 102 and Illinois 113 were both established in 1924, and originally both routes were numbered as Illinois 113. In 1940, the branch of Illinois 113 on the north side of the river became Illinois 113N, and the south branch became Illinois 113S. In 1961, Illinois 113N was renumbered as Illinois 102, and Illinois 113S became Illinois 113 again.