The West Walker River is a tributary of the Walker River, approximately 95 miles (153 km) long, in eastern California and western Nevada in the United States. It drains part of the Sierra Nevada range along the California-Nevada border in the watershed of Walker Lake in the Great Basin. The river is heavily used for irrigation in the ranching valleys along its lower course. Its waters are diverted along its upper course to form Topaz Lake along the California-Nevada border. It receives the Little Walker River from the south near its source in the mountains.