Masinloc is a first class municipality in the province of Zambales, Philippines. According to the 2010 census, it has a population of 44,342 people.
The disputed Scarborough Shoal (under the names Pulo ng Panatag and Bajo de Masinlóc) is claimed by the Philippine government as within the town's territorial jurisdiction. Due to the continued dispute over the shoal, this has negatively impacted fishermen of the community, reducing catch sizes and affecting other businesses.
Masinloc is politically subdivided into 13 barangays.
Located at Brgy. South Poblacion, the 18th-century San Andres Parish Church has been declared a National Cultural Treasure by the National Museum of the Philippines in July 2001.