State Route 600 (SR 600, OH 600) is an east–west state highway in the northwestern portion of the U.S. state of Ohio. The western terminus of State Route 600 is at U.S. Route 23 about 5 miles (8.0 km) west of Gibsonburg. Its eastern terminus is at U.S. Route 20 in the unincorporated community of Hessville approximately 4.25 miles (6.84 km) east of Gibsonburg.

All of State Route 600 exists within the confines of Sandusky County. This highway is not included within the National Highway System, a system of highways deemed most important for the country's economy, defense and mobility.

State Route 600 was first designated in 1937 along the routing that it maintains today between U.S. Route 23 and U.S. Route 20. No significant changes have taken place to the routing of the state highway since its inception.

The entire route is in Sandusky County.