The town gets its name from a former village of the native Luiseño people called awáanga, meaning 'dog place'. The Butterfield Overland Mail established a station 1.7 miles to the west of the current Post Office in 1858. It was at first called Tejungo Station and was located 14 miles east of Temecula Station and 12 miles northwest of Oak Grove Stage Station. The wooden building was located in a grove of trees a few hundred feet from the stage road. Soon, however, it became known as Aguanga Station after the name of the nearby Luiseño village.