The first Ilocano families from Paoay, Ilocos Norte arrived in the year 1830 and founded the first settlement that grew and developed into what is now the town of San Antonio. The site of the first community is somewhere near barrio Currilapa, now Barangay Antipolo. On their arrival, the first settlers found on this place a family of Aetas and later met a hunter of deer in the area named Don Salvador dela Cruz, a prominent resident of the pueblo of Cabangan. San Antonio was then a hunting region where indigenous hunters from the northern towns of Zambales would hunt and gather.

The village was first called Pamalisaraoan and later as PAMISARAOAN. PAMISARAOAN was given the status of a barrio, as part of Pueblo Uguit (now Castillejos) in 1836.

However, in the year 1846, when the barrio of Alasis or Aluciis, which then belonged to Cabangan, was made into a new pueblo, Barrio PAMISARAOAN was detached from Uguit and was subsequently attached to San Narciso. The town leader, Teniente Primero, in that period was Don Gregorio Bañaga, who governed from 1836 to 1849.

He was succeeded by Don Vicente Lacuesta in 1849 (governing as Teniente Absoluto), when San Antonio was finally recognized and given the status of a pueblo on May 12, 1849 as a result of two petitions for separation from the town of San Narciso. The first was in 1848 and the second was on March 8, 1849. The latter petition was signed by 31 top leaders of the community headed by Tiniente Primero Don Vicente Lacuesta.

The last mayor Teniente Absoluto was Don Santiago Ladrillono. He was succeeded by Don Dimas Pascasio as the first gobernadorcillo in 1856. The prominent citizens selected their leaders every year thereafter. In 1891 to 1898, Don Pablo Corpus was the only Capitan Municipal selected after which Don Felix Magsaysay was appointed as the first Presidente Municipal and many more followed up to 1931 to 1945.

San Antonio was the site of the US Naval Communications Station San Miguel, now the Naval Education and Training Command.

Now a Second Class Municipality, and under the leadership of Hon. Edzel L. Lonzanida, MD, San Antonio is experiencing a significant rise in tourist arrivals. With the improvements in tourism-related infrastructure like road rehabilitation, construction of first-class health facilities and major renovation of the San Antonio Public market, and over-all beautification and promotion of the town, San Antonio is truly on its way to become the crown jewel of tourism in Zambales and Region III.