The Brea-Olinda Oil Field is a large oil field in northern Orange County and Los Angeles County, California, along the southern edge of the Puente Hills, about four miles (6 km) northeast of Fullerton, and adjacent to the city of Brea. Discovered in 1880, the field is the sixteenth largest in California by cumulative production, and was the first of California's largest 50 oil fields to be found. It has produced over 412 million barrels of oil in the 130 years since it was first drilled, and retains approximately 19 million barrels in reserve recoverable with current technology. As of the beginning of 2009, 475 wells remained active on the field, operated by several independent oil companies, including Linn Energy, BreitBurn Energy Partners L.P., Cooper & Brain, and Thompson Energy.

Brea is a city in northern Orange County, California. The population as of the 2010 census was 39,282. It is 33 miles (53 km) southeast of Los Angeles. Brea is part of the Los Angeles metropolitan area.