State Highway 38 (abbreviated SH-38) is a state highway in the U.S. state of Oklahoma. It runs for 14.78 miles (23.79 km) in an irregular south-to-north pattern in eastern Alfalfa County, in the northwest part of the state. The highway begins at U.S. Route 64 (US-64) in Jet and extends to SH-11. SH-38 provides access to Great Salt Plains State Park, which the road skirts on the park's eastern edge. The road that is now SH-38 was added to the state highway system as SH-35 c. 1961. The highway was renumbered to SH-38 the following year.