K-8 is the name of two separate state highways in Kansas, United States. The southern highway is a 1.275-mile-long (2.052 km) road, linking Oklahoma State Highway 8 (SH-8) to the town of Kiowa. The northern highway is a 15.979-mile-long (25.716 km) road, linking U.S. Route 36 (US-36) near Athol to Nebraska Highway 10 (N-10) near the town of Franklin.