Influenced by multiple factors, distribution and variation law of the mean tidal range in eastern coastal China are quite complicated. Therefore, based on the continuous hourly observation data of 1 year at 21 tide gauges in eastern coastal China, annual mean tidal range and monthly mean tidal range are statistically analyzed.Furthermore, distribution of the annual mean tidal range and variation law of the monthly mean tidal range are also analyzed. The results show that besides the astronomical factor, runoff and morphology of the bay are important factors which can influence distribution and variation law of the mean tidal range. In the coastal area, influenced by the astronomical factor, monthly mean tidal range varies regularly. But in the river estuaries or the areas influenced by the acyclic factors, variation law of the monthly mean tidal range is irregular and complicated.