Under a certain condition where in the incident angle of waves is smaller than a critical angle，there appears a stem wave propagation along the wall.There are few researches on stem waves and they remain in the theoretical research stage at present.Based on the physical model test results of vertical breakwater typhoon damage restimulations and combined with existing domestic and foreign research results，the generation，characteristic and engineering impact of stem waves are analyzed initially.The results show that：1) The wave height and width of stem waves increase gradually along the wall，and the wave-height ratio increases fast and then slower.2) Different incident wave heights and directions have great impact on stem wave characteristics，and detailed rules need further study.3) Serpentine damage to vertical breakwater or damage to sloping breakwater that connected with vertical breakwater could be caused by stem waves.Similar arrangement should be avoided in project planning and design，and three-dimensional physical model tests should be used to verify the structure safety under stem waves.Related items for stem waves are not included in present specifications，and the research results can be used as reference for engineering design.