Abstract: Using chemical reaction kinetics simulation techniques, this study investigated the generation behavior and reaction kinetics of hydrogen produced from aluminum powder, magnesium powder, and Al-Mg alloy powders under conditions of varying moisture content. A comparative analysis was conducted on the temperature and pressure evolution, thermal sensitivity, hydrogen production characteristics, and key radical transformation patterns across four types of metal powders. The results show that metal dusts can underwent intense exothermic reactions in the presence of water. Compared to Al powder, Mg powder exhibited slower increases in both temperature and pressure upon moisture exposure. The reaction temperature and pressure of Al-Mg alloy powders were lower than those of Al powders, with the alloy containing 90% Al and 10% Mg exhibiting higher peak temperature and pressure than the alloy containing equal amounts of Al and Mg. During the moisture-induced reaction stage of Al, Mg, and Al-Mg alloys, the key elementary steps contributing to temperature rise primarily involved reactions with O₂ and H₂O. Al powder demonstrated the highest hydrogen generation capability at 50% moisture content, while Mg powder had the lowest hydrogen production rate and slowest rate of increase. The reactivity of Al-Mg alloys was significantly influenced by their compositional ratio. These findings can provide theoretical support for the precise prevention and control of spontaneous combustion and explosion accidents involving moisture-reactive and flammable metals.