Abstract: The paper briefly introduces the principle and structure of catalytic elements, studies the influence of internal factors such as shape, surface area and material on the thermal effect of catalytic elements. Through the measurement of the maximum surface temperature of the catalytic element under different test conditions, the most unfavorable conditions of the test are analyzed and summarized. By means of theoretical analysis, the factors influencing thermal ignition are studied, and finally the determination principle of intrinsically safe catalytic element is proposed.