Arkansas Highway 170 is a designation for two state highways in Washington County, Arkansas. The main segment of 17.31 miles (27.86 km) runs from Devil's Den State Park to West Fork. A shorter segment of 5.44 miles (8.75 km) runs from US Route 62 through Appleby before reconnecting with US 62.

AR 170 begins at a three-way junction with AR 74 and AR 220 in Devil's Den State Park. The route runs north, winding through steep Ozark topography. AR 170 serves as the southern terminus of AR 265 near the SEFOR reactor. The highway continues north through rural country, crossing over I-540. East of the expressway, AR 170 enters West Fork. The route enters town as Phillips St, turns south onto McKnight St, and turns left onto Main St. AR 170 continues to US Route 71, where the route terminates.

AR 170 begins at US 62 at Walnut Grove (northeast of Prairie Grove) and runs north/northeast to US 62 in Farmington. The route runs over the Cane Hill Road Bridge, and serves Appleby.

The entire route is in Washington County.

AR 170 follows the original 1926 alignment of AR 45 which later became US 62.