Abstract: The East China Sea is a typical shelf sea covered by shallow water. Seismic data there is strongly effected by some reflection interfaces, such as the water surface, the sea floor, and the Neogene bottom boundary. Multiple waves are common and the middle to deep seismic reflection signals are always masked, so the quality of deep images is poor. Conventional SRME or DWD methods can not effectively suppress the multiple waves. In this paper, therefore, a combined suppression method is proposed for solving the problem. Firstly, the DWD method is used to attenuate the seabed-related short-cycle multiples. Then converted the 3D GSMP to 2D so as to remove the long-cycle multiples related to the layered underground strata. Residual near-offset multiples are suppressed using PRIMAL, while the mid-to-far offset multiples are suppressed with high-precision RADON transformation. The processing results of the two-dimensional data from the East China Sea shelf proves that the methods mentioned above may effectively solve the multiple wave problems in the East China Sea, particularly for the reflection signals from the middle and deep parts, and thus imaging quality of the Mesozoic is much improved.