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Unconventional gas reservoir like shale reservoir can trigger a series of coupling interactions between shale deformation and gas transport during gas production process.Although continuum flow has been widely used in the evolution of porosity and permeability of unconventional gas reservoirs,the effect of different flow regimes in matrix system on shale gas reservoir performance is still unclear.Based on the complex gas storage and transport mechanism,a general dual porosity and permeability model is established which is applicable under in-situ stress conditions.The dual porosity model is implemented into a fully coupled finite element model of shale deformation,gas flow and transport in matrix system and fracture system.The modeled gas production rate is in good agreement with the field data from Marcellus shale reservoir well published in the literature.Further,a sensitivity analysis of parameters affecting shale gas reservoir performance,including the intrinsic permeability and porosity of matrix system,initial reservoir pressure,fracture spacing and fracture aperture,is conducted.Besides,a comparison of matrix-fracture dual-porosity model considering three different gas flow regimes is conducted both theoretically and numerically:(1)continuum flow in both matrix system and fracture system;(2)slip flow in matrix system and continuum flow in fracture system;(3)Knudsen diffusion,Fick's law in matrix system and continuum flow in fracture system.The simulation result shows that different flow regimes in matrix system can significantly influence shale gas reservoir performance.