State Route 617 (SR 617, OH 617) is a short east–west state route in northeastern Ohio, existing entirely within Mahoning County. The western terminus of OH 617 is at OH 165 in the unincorporated community of New Springfield. Its eastern terminus is at the Pennsylvania State Line just southeast of the hamlet of Petersburg, where OH 617 turns into PA 351.

The journey of OH 617 begins at the intersection of OH 165 and Garfield Road (Mahoning County Road 8 to the west) in the Mahoning County hamlet of New Springfield. Heading east into Springfield Township, OH 617 comes upon its intersection with Beard Road (County Road 167), passes by some homes, then curves through some woods and resumes a due east trend, passing by both woods and farmland, residences and commercialized businesses, alike, along the way. Next, OH 617 meets Unity Road (County Road 175), and then a little further along the route, Hofmeister Road (County Road 189). There, OH 617 follows a gradual reverse curve that takes it southeasterly, then back to the east. As the number of homes along the route starts to increase, especially on the south side, OH 617 turns again to the southeast, then easterly yet again, where it comes upon Waterford Road. Further east, OH 617 enters into the unincorporated community of Petersburg, where the route bends to the northeast, and arrives at its western junction with OH 170, which comes into the intersection from the south. OH 170 and OH 617 duplex for approximately two blocks to the main intersection within the hamlet, where the two routes arrive at the eastern split of the duplex. From the intersection: OH 170 heads to the northwest; County Road 8, which goes on to become PA 108 just 1-mile (1.6 km) from the intersection, resumes to the northeast; and OH 617 goes to the southeast.

Traversing southeast from OH 170, OH 617 passes through a primarily residential area, intersecting a few side streets as the route makes its way out of Petersburg. Once back into a more rural setting, OH 617 passes through farmland, with a few homes dotting the landscape. Arriving at the Pennsylvania State Line, OH 617 comes to an end. The highway continues into the Keystone State as PA 351.

OH 617 was designated in 1937 along the path that it currently occupies. No major changes have taken place to the routing of OH 617 since it made its debut.

The entire route is in Springfield Township, Mahoning County.