With the rapid increase of global energy consumption

the conventional natural gas resource is in shortage and difficult to meet the increasing demands. As a kind of unconventional gas

shale gas has a potential wealth of natural resources and the advantage of low carbon emission. With the commercial exploitation in America and Canada

shale gas has been drawing more and more attention. However

due to the tightness and low permeability of shale

shale gas is extremely difficult to produce. Therefore

understanding pore structure of shale as well as gas adsorption and diffusion is of great importance for the resource assessment and effective exploitation. In this review

domestic and overseas development progress of shale gas resource has been outlined

and the pore structures as well as the features of the shales are elaborated. The progress in molecular simulation of adsorption and diffusion of shale gas is summarized

and the perspective for shale gas is also provided.