Mississippi Highway 42 is a state highway in southern Mississippi. MS 42 runs in an east/west direction for 116.0 miles (186.7 km), serving seven Mississippi counties: Wayne, Greene, Perry, Forrest, Lamar, Jefferson Davis, and Lawrence. Portions of this highway run parallel to the Longleaf Trace. The length of highway between Interstate 59 and U.S. Highway 11 in Forrest County, just outside Petal is known as the Evelyn Gandy Parkway.

Greene County is a county located on the southeast border of the U.S. state of Mississippi. As of the 2020 census, the population was 13,530. Its county seat is Leakesville. Established in 1811, the county was named for General Nathanael Greene of the American Revolutionary War.