The characteristics and genesis of storm current in Xiyang channel of the radial sand ridges area were analyzed according to the hydrology data (1980 and 2001) and new measured (2008) hydrology-sediment data. Results indicate that the fairly large value and minor variation of direction in the storm current velocity, and the sediment concentration at each observation level responds well to the velocity. For one hand, tidal pore generally resulted from the special bell-mouth topography in Xiyang channel, while no abnormal change in tidal level occurred with storm currents. On the other hand, there exists a surge of velocity and sediment concentration in storm current at each level instantaneously with maximum velocity of 3.71m/s and maximum sediment concentration of 14.94kg/m3 at the bottom. However, wind stress cannot generate such large velocity maintaining huge energy to raise the massive sediments from the bottom current with a depth of 10m. Besides, no storm current was observed at the neighboring stations at the same time. Therefore, both the seiche and wind stress are not the essential factors for the genesis of storm current. A further study on the formation mechanism should be conducted based on the convergence of tidal current and special topography henceforth.