Abstract: Gas hydrate is the hotspot of researching to the petroleum geologists and researchers in present world, and it is also the central caring issue to the scientific, technologic, energetic and environmental fields in the new century. This paper would take a analyze to the issue. The purpose is to awake a better investigation. It would be beneficial to the gas hydrate pre-research and the petroleum exploring developing to the deep-water area of the epicontinental basins in the north part of the South China Sea.