Abstract: Gas-liquid-solid complex flow was complicated in the production of a condensate gas reservoir with wax deposition. Under experiment research results on the porous flow mechanism, the porous flow model was described to reveal the complex flow law. According to the phase change law for wax deposition and dew point line curves, and the change of the saturation of condensate gas with phase properties, gas-liquid-solid was transformed with phase change, which would result in the change of distribution of fluid pressure and influence or alter the characteristic and the process of condensate gas percolation flow. Under experimental results of wax deposition and phase change, the mechanical characteristics of fluids flowing through porous media and the relevant physicochemical problem were all summed up as solving the gas-liquid-solid coupling mathematical model. After considering the phase change action between condensate gas and condensate liquid, wax deposition interlarded with interracial drag force and capillary pressure engendered in the process of phase change. Numerical simulation results proved that the flow resistance increased and the production output decreased owing to wax deposition. The model could reveal the physical essence of porous flow.