The East Texas Oil Field is a large oil and gas field in east Texas. Covering 140,000 acres (570 km) and parts of five counties, and having 30,340 historic and active oil wells, it is the second largest oil field in the United States outside of Alaska, and first in total volume of oil recovered since its discovery in 1930. It is a component of the Mid-Continent Oil Province, the huge region of petroleum deposits extending from Kansas to New Mexico to the Gulf of Mexico.

The field includes parts of Gregg, western Rusk, southern Upshur, southeastern Smith, and northeastern Cherokee counties in the northeastern part of the state. Overall the field is about 45 miles (72 km) long on the north-south axis, and five miles (8 km) across. Interstate 20 cuts across the field from east to west, and the towns of Kilgore, Overton, and Gladewater are on the field. At one time, downtown Kilgore had more than 1,000 active wells clustered in a tight area, making it the densest oil development in the world.