It runs for 21.47 miles (34.55 km)[1] north and south through the eastern part of the county, connecting U.S. Highway 287 near the Oklahoma-Texas state line to US-56 in Keyes.

The only other highway it intersects with is US-64/412/SH-3, three miles (5 km) south of Keyes.

SH-171 was established circa 1974 with its present-day routing and termini, and may have initially been numbered SH-170.

Approximately five miles (8.0 km) north of the terminus, SH-171 crosses the intermittent Beaver River (a local name for the North Canadian River).

SH-171 continues north, passing along the eastern edge of the town of Keyes.