The purpose of this experimental investigation was to examine the effects of ultrafine water mist on explosions caused by methane and coal dust hybrids that occurred inside of a closed vessel. In this study, we built a small-scale semi-closed visualization experimental platform and ran simulations to study the effects of four factors on the explosion of methane coal mixtures: the amount of ultra-fine water mist sprayed, the volume fraction of methane, the position of the methane inlet, and the amount of time it took to premix. This allowed us to gain a deeper understanding of the repressive effect of this water mist on methane explosion. The findings demonstrate that ultrafine water mist is capable of suppressing methane explosions, with a notable inhibitory effect on 10% methane. This inhibitory effect becomes stronger with increasing amounts of sprayed ultrafine water mist. The effect of methane volume fraction on the maximum explosion overpressure Δ