In this study, the risk of coastal inundation due to storm surge in coastal of Thanh Hoa province for several scenarios of typhoon landfall the area with average height tidel cases is simulated by a couple model of surge, wave and tidel (SuWAT model). In which, the SuWAT model is developed with a moving boundary treatment to simulate inundation due to storm surge. Simulation results show that with typhoon level 12 and simulation time of 90 hours since the typhoon appear, at 71 hours, the water level in Thanh Hoa coastal area started to rise, after 73 inundation occure in some low-lying coastal areas and along river basins, at 79 hours, most of the areas with rising water were at their deepest. The area with the largest and deepest flooded area is along the coast of Hau Loc district, around the basins of Yen river, Ma river, Truong Giang river and Len river. In the case of a typhoon level 15, the total inundation area is up to 153.2 km2. These are the initial research results on coastal inundation due to storm surge, which serve as a basis for further model development as well as implementation in many different scenarios in terms of terrain and storm intensity.