Shale gas is an unconventional and particularly important energy resource. Since the onset of the 21st century, the development of shale gas reservoirs has attracted much attention. In general, the composition of shale is complex and can be divided broadly into organic and inorganic materials. However, both pore characteristics and formation mechanisms of water saturation present in these organic and inorganic materials are different, which result in various gas-liquid-solid interactions and gas production mechanisms. At present, most of the research on shale gas reservoirs has been qualitative in nature, and even fewer studies have been theoretically quantified. Therefore, an understanding of interactions that take place between methane-water-shale is an ongoing issue. To better understand these interactions, a number of issues must be resolved. First, the water content in shale's organic and inorganic materials needs to be quantified. Second, diffusion and flow models of shale gas within nano-scale pores must be coupled. Finally, the influence of a shale reservoir's water saturation on the diffusion and flow of gas must be further studied. Finding solutions to the issues outlined above will help further our understanding of shale gas reservoirs. In this thesis, distributions and evolution of both gas and water present in shale's mixed organic and inorganic pores will be analyzed, and the influence of reservoir water on shale gas production will be further quantified. This thesis lays a theoretical foundation that can be used to reasonably evaluate a shale reservoir's productivity under realistic water conditions, thus improving upon theories of shale gas reservoir development and further promoting the rational and effective development of shale gas resources.