The Russell Ranch Oil Field is an oil and gas field in the Cuyama Valley of northern Santa Barbara and southern San Luis Obispo Counties, California, in the United States. Discovered in 1948, and reaching peak production in 1950, it has produced over 68 million barrels (10,800,000 m³) of oil in its lifetime; with only an estimated 216,000 barrels (34,300 m³) of recoverable oil remaining, and having produced around 66,000 in 2008, it is considered to be close to exhaustion.