With the level of B3LYP/Lanl2dz of density functional theory and advisable adsorption models designed, the adsorption properties of the most stable cluster of Ni2Fe2P were calculated, and four stable configurations with the adsorption of hydrogen were gained. The geometries and HOMO contributions of 3d orbital of metal atoms and energy level properties of adsorption configurations were concerned and their Infrared Spectrum were simulated and predicted. The bond lengths and bond orders and vibration frequencies concerned synthetically, the adsorption mechanisms of hydrogen molecular on amorphous alloys Ni40Fe40P20 surfaces were discussed in the microcosmic aspect. The hydrogen molecules adsorbing on the clusters were dissociated. In the clusters′ Infrared Spectrums of hydrogen adsorption, there were the vibration peaks with the frequency less than 500 cm-1 caused by metal atoms and other vibration peaks with the frequency more than 500 cm-1 caused by hydrogen atoms. Compared with the energy level DOS of the clusters before and after adsorption, it was found, that the new adsorption activity sites generated after the adsorption of hydrogen, as well as easy way for metal atoms providing electrons and participating subsequence reactions were gained.