Abstract: Mine gas explosion affects mine safe production, and gas explosion prevention technology has always been the top priority in mine safety. In addition to explosion venting, explosion suppression is also an efficient prevention technology. However, most of the gas explosion inhibitors used in production are not effective. This study provides a catalytic composite powder inhibitor, which uses the traditional fire extinguishing agent KHCO3 as the basic material, adding an appropriate amount of ferrocene and a small amount of grinding aids and desiccants by a planetary ball mill. Through the standard 20 L spherical explosive device, the influence of catalytic composite powder on the maximum pressure, the maximum rate of pressure rise, and other relevant characteristic parameters of the gas explosion were tested. According to the de agration index, the mitigating hazard effect of each composite powder inhibitor was analyzed in detail. It also elucidated the inhibition mechanism based on the characteristic parameters of the composite powder inhibitor. Results show that the addition of ferrocene significantly improves the agglomeration and pyrolysis performance of traditional KHCO3 inhibitors. The desiccant increases the hydrophobic properties of the composite inhibitor, making it easier to store and transport under normal temperature and pressure. The planetary ball mill greatly reduces the particle size of the composite explosion inhibitors. After testing, the volumetrically weighted average particle size of the catalytic composite explosion suppressor is 40.61 μm. The optimum inhibition concentration of catalytic composite powder is 0.1 g/L. The composite powder inhibitor demonstrates a better suppression effect. The maximum pressure reduces 31.6% and both the maximum rate of pressure rise and the deflagration index reduce 93.0% when the total content ratio of ferrocene, KHCO3, grinding aid, and desiccant reaches 3∶16∶1.