Yijhu Township is located at the south west of Chiayi County, neighboring to Luocao Township in the east, Puzi City in the northeast, and Budai Town in the northwest with Bajhang River in the south as the boundary to Tainan County. Yanshui Township, Tainan County is just located in the opposite side of the river. Area: Yijhu Township is comprised of twenty-two villages, with the total area of 79.2925 km2, with 46.6341 km2 of agricultural area and a planned urban area of 1.615 km2.
Landform and terrain: The contour of Yijhu Township looks like that of Taiwan. Neighboring to the sea, it is flat in topography. With the Central Highway running through the township, the south of Bajhang River flows along, working as a natural boundary with Tainan County.