The area around Pearl River estuary is one of the most important economic zones in China where the effect of human activities is acute. The geological environment which is complex and various hazardous geological characteristics are distributed. For the sake of submarine infrastructures’ safety, both construction and maintenance, the authors need to evaluate the geological hazard risk. The results show that 58% of the research area is stable, while 25% of the research area is less stable. The distribution of unstable areas is near the northeast and northwest faults. Despite the fact that the unstable area is limited, the authors should pay more attention to these areas when design and construct submarine infrastructures.