TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Material: The material further comprises a metal particle having a maximum diameter of less than or equal to 500 nm and dispersed in the amorphous phase. The metal particle contains Ni, Fe and/or Pd. In the material, in a hydrogen storage/release measurement under an applied hydrogen pressure of vacuum to 10 MPa, a measurement temperature of 60 degrees C, and a convergence time of 30 minutes, the hydrogen storage material stores a greater amount of hydrogen as the applied hydrogen pressure increases without formation of a plateau. Preferred Method: In the method (M1), in mixing step, weight ratio of the AlH3 to a total of the MgH2 and the TiH2 is 55/45-95/5, and weight ratio of the MgH2 to the TiH2 is 1/9 to 9/1; a metal particle having a maximum diameter of less than or equal to 500 nm is further added. In the method, a weight ratio of the AlH3 to a total of the MgH2, the TiH2, and the metal particle is 55/45 to 95/5. The hydrogen atmosphere has a hydrogen pressure of 0.1-2 MPa. EXAMPLE - Aluminum chloride (AlCl3) (13 g) was added to and dissolved in diethyl ether solution (300 ml) containing lithium aluminum hydride (LiAlH4) (1 mol/l), and was reacted at the ambient temperature until gas generation stopped. Then, LiCl precipitated in the solution was removed by filtration, and the filtrate was exposed to reduced pressure for 1 hour using a vacuum pump to evaporate diethyl ether. The residue was dried under reduced pressure for 1 hour at each temperature of 40 degrees C, 60 degrees C and 80 degrees C, to obtain particulate synthetic product (2 g). The steps were repeated to prepare aluminum hydride (AlH3) particles (6 g) in total. The prepared AlH3 particles (0.7 g) were mixed with magnesium hydride (MgH2) (0.1 g) and titanium hydride (TiH2) (0.2 g) in an agate mortar to prepare a mixed powder. In the mixed powder, the weight ratio of AlH3:MgH2:TiH2 was 7:1:2. The mixed powder was enclosed together with a crushing ball in a pot. In this step, the enclosure was carried out in a hydrogen atmosphere, and hydrogen was introduced to the pot such that the internal hydrogen pressure of the pot was 1.5 MPa. The pot was sandwiched between a press shaft and a rotatable table on a disc-shaped base plate of a planetary ball milling apparatus and subjected to a ball milling treatment. A force of 16G was applied to the mixed powder under the condition. The ball-milled powder was dehydrogenated to produce a final product. The final product was confirmed by X-ray diffraction pattern as given in the specification.