Based upon the long-term observation of field data, a two-dimensional numerical model is applied to simulating the tidal flow covering from the neap tide to spring nde m the radial sandbank area m the southern Yellow Sea. From the development of tidal current ridges under the hydrodynamic action, multi-purpose analysis and study are carried out, which include the propagation process of tidal wave, the distributions of ndal wave energy rate and tidal range, the tidal ellipses and traces. It is shown that the tidal current is the major dynamm factor for the formation and development of the radial sandbanks, and the differences of tidal wave energy rate and current strength determine the distract plane shapes of ridges and troughs in this region.