The samples of gas hydrate have been successfully obtained by drilling in the Shenhu area of northern South China Sea，it is confirmed that the Pearl River Mouth Basin is a gas hydrate-rich area.By means of quantitative basin modeling research of tectonic subsidence history of deep water area in Pearl River Mouth Basin，tectonic subsidence has been generally characterized by acceleration from north to south and from west to east in the research area since the Late Miocene.From the Late Miocene to Pleistocene，deep water area in the basin experienced the variation process of tectonic subsidence effect that was from weak to strong: The average tectonic subsidence rate was 67 m/Ma in the Late Miocene(11.6～5.3 Ma)，the average tectonic subsidence rate was 68 m/Ma in the Pliocene(5.3～1.8 Ma)，and the average tectonic subsidence rate was 73 m/Ma in the Pleistocene(1.8～0 Ma).Moreover，the major reasons which causing these changes were Dongsha tectonic event from the end of the Middle Miocene to the end of the Late Miocene and Taiwan tectonic event from the Pliocene to the Early Pleistocene: Dongsha tectonic event(10～5 Ma)makes fault block uplifting and sagging，rise area eroding，and waning of movement intensity and structural deformation from east to west，which caused stable subsidence of deep water area in the basin;Taiwan tectonic event(3 Ma)thoroughly changed the tectonic framework of deep water area in the basin，which kept on subsiding and was subsiding more southward because of gravity balance.Overlaying the developed areas of BSR and plane map of tectonic subsidence rate，it was discovered that more than 80％ Bottom Simulating Reflector(BSR) tend to be distributed in the transfer zone between uplift and depression that the average tectonic subsidence rate ranged from 75 m/Ma to 125 m/Ma and changed rapidly.