Abstract: The sedimentary basins in the Northern South China Sea are rich in oil and gas. Earthquake activities have important and directly influences on the stability of these sedimentary basins. This paper deals with the distribution of main fault zones and their activity characteristics in the studied area. On the basis of the seismic data in the Northern South China Sea, this article made a map on fault zone distribution and earthquake epicenter distribution for the region of the Northern South China Sea. Earthquakes in the region are grouped into three sub-zones, i.e. the coastal area of Guangdong, the coastal area of Fujian, and the Zhujiang River mouth and shallow water area of Taiwan. Comparatively studies are carried out based on the seismic parameter b and the earthquake acceleration of the three seismic sub-zones. The b values are 0.9498, 0.6452 and 0.4865 in the coastal area of Guangdong, the coastal area of Fujian, the Zhujiang river mouth basin and shallow water area of Taiwan respectively. And the earthquake acceleration changes between 0.115~0.379 g. This research work may provide a basis for stability analysis and evaluation on sedimentary basins in the Northern South China sea.