Coastal erosion is one of the major coastal problems in Indonesia. A fishing port was constructed about 5 km downdrift side of Pebuahan coast which is the target site in this study, and immediately after the fishing port was constructed, significant erosion began on its downdrift side. Meanwhile, sediment accumulates year by year on the updrift side of the fishing port and this sediment has already deposited inside the fishing port. Ministry of Public Works has been continuously implementing the construction of revetment to prevent coastal erosion at the downdrift side but these countermeasures will not solve the problems of coastal erosion and sedimentation in the fishing port. Therefore, the purpose of this study is to examine the feasibility of a new countermeasure of erosion prevention, namely, a sand bypass from the sand accumulation area at updrift side of a fishing port to the downdrift side of the longshore sediment transport, through long-term shoreline change analysis using satellite image, field surveys and numerical analysis.