The mechanism of catalytic hydrogasification of coal remains unclear. This article aims to gain a deeper understanding of the mechanism by examining the effect of spillover hydrogen (SH) on the catalytic hydrogasification activity of Fe-group metals. The SH from CoCa/Al2O3 and CoCa/SiO2 was performed in a fixed bed reactor to enhance the char catalytic hydrogasification. Experimental results revealed that SH enhanced the CH4 yield of all samples. The presence of SH exerted a distinct effect on Fe group metals catalyzed hydrogasification, significantly improved performance for Fe catalyst, relatively minor effect for Ni catalyst, and negligible improvement for Co catalyst. DFT calculation results demonstrated that different metals show distinct abilities on C-C breakage and hydrogen dissociation, which leads to different rate control steps for various metal catalysts in the catalytic hydrogasification. The rate control steps of catalytic hydrogenation by iron group metals are analyzed, and the results agree with the DFT calculation and experimental results.