Sihhu Township is located near the southwest coastline of Yunlin County and situated at about 102°13’ east longitude and 23°38’ north latitude. It borders Beigang Township and Yuanjhang Township to the southeast, Shueilin Township and Kouhu Township to the south, Old Huwei Stream, Dongshih Township and Taisi Township to the north and Taiwan Strait to the west. The length of Sihhu from east to west is 14.5 km and the width from north to south is 12.6 km. The cat-shaped Township covers 7711.89 hectares of plain land with 5944.04 hectares of farmland.
Sihhu Township is a typical coastal rural village with all kinds of topography, such as Santiaolun near the port. During the Japanese colonial period, Japanese people built garrison house, fort,, irrigation canals and ensigns. After years of geographical change, those constructions sank into the ocean and could only be seen during ebbs.