The Saint Augustine Church, commonly known as the Paoay Church, is the Roman Catholic church of the municipality of Paoay, Ilocos Norte in the Philippines. Completed in 1710, the church is famous for its distinct architecture highlighted by the enormous buttresses on the sides and back of the building. It is declared as a National Cultural Treasure by the Philippine government in 1973 and a UNESCO World Heritage Site under the collective group of Baroque Churches of the Philippines in 1993.
The town of Paoay was originally called "Bombay" as the earliest inhabitants believed to have come from India. The earliest historical record of the area dates back to 1593, becoming an Augustinian independent parish in 1686. Building of the present church was started in 1694 by Augustinian friar Father Antonio Estavillo, completed in 1710 and rededicated in 1896. Some portions of the church was damaged in the 1865 and 1885 earthquake but was later restored under the initiative of former First Lady Imelda Marcos.