Sibalom River is the longest river in the province of Antique in Panay island Philippines. With a total length of 72 kilometres (45 mi) and a drainage basin covering 682 square kilometres (263 sq mi), it is the largest river system in Antique and fourth longest in Panay after Panay River, Jalaur River, and Aklan River. It is located in Sibalom and San Remigio. Along with its main tributaries Mao-it River and Tipulu-an River, it forms the 5,511.47-hectare (13,619.1-acre) Tipulu-an and Mao-it River Watershed Forest Reserve (now known as Sibalom Natural Park) which was proclaimed a natural park on 23 April 2000.