Xihu Sag is the main hydrocarbon-rich area in the East China Sea shelf basin, which has the characteristics of deep burial of main reservoirs, complex fault system and large lateral variation of reservoirs. The original seismic data has low signal-to-noise ratio, narrow azimuth and insufficient transverse sampling density. Consequently, it is difficult to meet the needs of accurate imaging and reservoir description. Based on the analysis of the original data, this paper demonstrates the high density and wide azimuth seismic acquisition technology with deep-tow, and introduces the latest application effect in Xihu Sag. The results show that the new data has better imaging quality than the original data. It is concluded that the application of the new acquisition technology can obtain smaller bin size, higher fold, more low frequency information and wider azimuth, which is beneficial to improve the reflection energy, signal-to-noise ratio of deep and middle targets and the imaging quality of faults. As a result, the reliable seismic data for reservoir description and hydrocarbon prediction can be provided.