Abstract: For channel-type positive pressure standard leak (CTPPSL) filled with porous media, it is difficult to control and obtain the variation of leakage rate with temperature in actual measurement due to the influence of temperature. This paper establishes a mathematical model using numerical simulation to describe the flow mechanism of fluid inside CTPPSL filled with porous media. The three-dimensional surface graph of the combined influences of different inlet temperatures and pressures, porosity, and pore diameter on the leakage rate of CTPPSL was analyzed, and the velocity field distribution was provided. The results show that the leakage rate of CTPPSL decreases with the increase of inlet temperature and increases with the increase of inlet pressure, porosity and pore diameter. When the inlet pressure is 700 kPa, for every 2 K difference in temperature, the relative error of the obtained leakage rate is 0.54%. While the inlet temperature is 291 K, the growth rate of the leakage rate obtained when the porosity \varepsilon increases from 0.85 to 0.95 is 63.5% higher than that obtained when the porosity ε increases from 0.55 to 0.65. Besides, within the same variation range of porosity, the growth rate of the leakage rate of CTPPSL increases with the increase of pore diameter. Based on the research results, the conclusion was drawn that the leakage rate of CTPPSL can be effectively controlled and adjusted under the combined action of temperature, pressure, porosity and pore diameter. This research provides valuable reference significance for the processing design of CTPPSL in the future and controlling the rate of change of the leakage rate.