The invention relates to a dynamic physical simulation method for gas reservoir development and a device thereof, which reproduce a pressure and output variation law in a development process. The method comprises the steps of: acquiring cores of single gas wells and preparing a natural core of gas reservoir; arranging the cores according to permeability and porosity characteristics of the known single gas well control reservoirs from near well to distant well; and recording the pressure, flow and cumulative flow of different position points of the cores, drawing a characteristic curve, and simulating the production dynamic characteristics of the single gas wells and the dynamic physical variation of the gas reservoir development. The device consists of a high-pressure gas source, core holders, pressure sensors, a pressure regulating valve, mass flow controllers and a computer, wherein more than two core holders are combined, and outlet ends of the core holders are connected with the pressure sensors and the mass flow controllers. The method can simulate a gas reservoir environment and a gas reservoir development mode, reproduce the pressure and output variation law of homogeneous reservoirs and non-homogeneous reservoirs in the production process of the gas reservoir, and realize the study on a dynamic law of the gas reservoir development by the physical simulation method.