Abstract: Taking the Wufeng Formation-Longmaxi Formation shale gas reservoirs in Sichuan Basin and its periphery as examples, this paper summarizes the geological characteristics of high-pressure and over-pressure shale gas fields in complex tectonic regions, compares and analyzes similarities and differences between normal pressure and high-/over-pressure shale gas reservoirs. According to the distribution characteristics of tectonic reworking and gas reservoirs, this paper proposes a classification scheme for normal pressure shale gas reservoirs, and divides the normal pressure shale gas reservoirs in southern China into three types, i.e., intra-basin type, basin margin transition type and extrabasinal residual type. The research shows that the shale gas reservoirs of the extrabasinal residual type has the characteristics of small continuous distribution area, well-developed fractures, low formation pressure coefficient, low free gas ratio, small crustal stress and large difference in bidirectional horizontal stress. For the normal pressure shale gas reservoirs in complex tectonic regions outside the basin, this paper proposes that TOC greater than 3%, porosity above 3%, and gas content more than 3 m³/t can be used as the basis for selecting beneficial development zones.