Mount Holly is an unincorporated village located in the U.S. state of Arkansas. It is within Union County at the junction of Arkansas Highway 57 and Arkansas Highway 160 approximately 18 miles west-northwest of El Dorado. It coordinates at 33°18′09″N 92°57′18″W. The elevation is 262 feet above sea level. According to the recent census, the total population of Mount Holly is 336. The population density is about 5 people/sq mi. Racial makeup mostly consists of 82.74% White. It has Zip code 71758.