State Route 198 or SR-198 is a 1.686-mile (2.713 km) long route that serves as a connection between State Route 30 and State Route 239 in Clayton.

The western terminus of SR-198 is located at its intersection with SR-239 in downtown Clayton. From this point, the route travels in an easterly direction before turning to the south in route to its eastern terminus at SR-30.

The entire route is in Barbour County.