Golden Beach in south Taiwan is widely known and has been attracting many beachgoers. In recent years, this beach has been eroded and measures to restore the sandy beach are required. The cause of the beach erosion was investigated on the basis of bathymetric survey data. In the study area, northward longshore sand transport, which was induced by the wave-sheltering effect of Anping Harbor, prevails, and the rate of transport was estimated to be 1.25×10 5 m 3 /yr with the conditions of the depth of closure (h c ) of -6 m, the berm height (h R ) of 2.2 m, and the characteristic height of beach changes (h) of 9.2 m.