Illinois Route 151 is a north–south state road in southern Illinois located entirely within Jackson County. It runs from Illinois Route 3 in rural Jackson County to Illinois Route 4 in Ava. This is a distance of 7.84 miles (12.62 km).

Illinois 151 serves as a connector through the northwest portion of Shawnee National Forest. It also is the access road to the Jackson Creek Recreational Area.

SBI Route 151 originally ran from Steeleville to Murphysboro; this was absorbed into Illinois Route 43 in 1937, and eventually became part of Illinois 4 in 1964. In 1940, Illinois 151 was placed onto its current route.

The entire route is in Jackson County.