Recent researches of marine gas hydrate indicate that the formation, migration and distribution of the gas hydrate have close relationship with deep-water depositional systems. With the development of deep-water observations and drilling technology and the wide use of high-resolution 3D seismic data, the studies on deep-water depositional systems have made great progress. Consequently, the analysis and description of the deep-water deposits in the shallow layers in a promising target area have become a hot and difficult question in gas hydrate exploration. This paper aims to provide a systematic study on the progress of the deep-water depositional system from following aspects:source to sink system, internal architecture description, and complex controlling factors. In combination with the current situation and problems of gas hydrate exploration on the northern continental slope of the South China Sea, some suggestions were proposed, including the analysis of deep-water depositional types and background, the description of the internal architecture and evolution of the deep-water deposits in the shallow layers, and the relationship between the deep-water deposits and gas hydrate in the shallow layers, in order to provide a reference for research and exploration of gas hydrate in the region.