Structural changes of the CeFe 2 Laves phase compound during the hydrogen absorption and desorption process have been investigated by X-ray diffraction, transmission electron microscopy, thermal analysis and magnetic property measurements. The transition from the crystalline to the amorphous state has been confirmed to occur below about 500 K, where the formation of the elemental hydride, CeH 2, is virtually hindered. The whole crystalline phase does not change to the amorphous state in a uniform manner, but a part of the crystalline phase changes to the amorphous one which grows with further hydrogenation. The requirements for alloys to undergo hydrogen-induced amorphization were discussed. The proposed requirements are for alloys 1. (i) to have the Laves structure, 2. (ii) to contain hydride-forming elements 3. (iii) to have either a low melting point or a tendency to decompose into other intermetallic compounds.