Abstract: East China Sea is an important part of West Pacific Tectonic Zone and a window to discuss the formation and evolution of west edge of the Pacific Ocean. Upward continuation has been used as a common method to process original gravity anomaly through strengthening deep anomaly and weakening local anomaly and it's important to deep structure research. Wavelet analysis is an effective tool to separate gravity and magnetic fields and it can not only extract deep anomaly but also separate regional and local anomalies. Based on the new Bouguer gravity anomaly data of East China Sea and adjacent regions,upward continuation and wavelet analysis methods were utilized in the present study. Bouguer anomaly results of 20 km upward and the 4th order wavelet approximation were compared and buried Moho depth was calculated and the characteristics of deep structures were analyzed. Anomaly of the 4th order wavelet approximation represents Moho and the 4th order detail wavelet result represents depression and uplift of East China Sea.