A method of pressure loss analysis for explosion-proof valve with flame arrester sheets was presented. The structure and operational principle of the explosion-proof valve was analyzed and its numerical analytical model was established. The effect of different inlet temperature and inlet pressure on the pressure distribution inside the valve was analyzed using computational fluid dynamics (CFD) technology. The result showed that the influence of inlet temperature on pressure distribution was small while that on pressure distribution was significant. The fitting function for the pressure on the surface of  each section of the basic element under different inlet pressures was done. Besides the function relationship for the pressure on the surface of each section and inlet pressure and the amount of the section was obtained. This function relationship could efficiently reflect the pressure loss and calculate the pressure of the surface  of each section of the basic element, which is of importance to the design of explosion-proof valve with flame arrester
 sheets.