Abstract: Tidal energy is a renewable and pollution-free energy with huge reserves.The research on the distribution characteristics of tidal energy resources is of great practical significance for the development and utilization of the tidal energy in China.At present,the investiga‐tion of tidal energy resources is mostly the analysis and statistics of discrete point resources,and there is a lack of continuous calculation of and research on the tidal energy resources in the whole sea area.In order to understand the distribution of resources in the whole sea area,a numerical model of the tidal wave motion in the East China Sea is established.The numerical simulation results are in good agreement with the coastal stations and the co tidal map given by predecessors based on measured data.On this basis,combined with the numerical simula‐tion results and the national standards issued in recent years,the spatial distribution laws of the technical exploitable level,theoretical aver‐age power and annual reserves of tidal energy resources in the East China Sea are evaluated.The results show that due to the change of lunar orbit,the annual average tidal range variation period（about 19 years）and phases are equal,but amplitude is different.Most sea areas in the East China Sea have a small average tidal range and are poor in tidal energy resources,but a small number of sea areas such as the West Bank of the Korean Peninsula,Hangzhou Bay and Taiwan Strait have an average tidal range of more than 4.5 m.They are rich or relatively rich in tidal energy resources,and their theoretical average power and annual potential tidal power reserves can above 2×10~3kW/km~2and 2×10~8kWh/（a·km~2）.The average tidal range in most coastal areas of Zhejiang,Fujian and Northern Jiangsu is around 3.0～4.0 m,which is mainly the available area of tidal energy resources.The theoretical average power and annual potential tidal power reserves are about 1.3×10~3kW/km~2and 1.3×10~8kWh/（a·km~2）.Compared with the average tidal range,the spatial distribution of annual potential tidal power reserves and theoretical average power in different sea areas is more uneven.