State Route 537 (SR 537, OH 537) is a short east–west state highway in southeastern Ohio. At a length of just shy of 5 miles (8.0 km), State Route 537 is located entirely within southwestern Monroe County. The state route's western terminus is at State Route 260 approximately 3.5 miles (5.6 km) southeast of the unincorporated community of Sycamore Valley, and its eastern terminus is at State Route 26 1 mile (1.6 km) south of the village limits of Graysville.