The present invention provides a high capacity hydrogen storage material in which a plural mesopore channels and fractal networks of nanopore channels communicating therewith and connecting to the micropores are formed in a microporous material, wherein a plural metal particles are formed on the surface of the mesopore and nanopore channels and of the micropores. In another embodiment, the present invention also provides a method for making the hydrogen storage material through oxidizing the microporous material so as to form a plural mesopore channels and fractal networks of nanopore channels, both of which are connected to the micropores to form a base for the deposition of metal particles capable of decomposing hydrogen molecules into hydrogen atoms. The high capacity hydrogen storage material is capable of increasing the capacity of hydrogen storage, and besides, the oxidizing process for making the hydrogen storage material is simple and has merits of saving cost.