This invention belongs to the field of nanomaterials. Specifically relates to a kind of hierarchical porous material and its preparation method. A kind of hierarchical porous material is disclosed, and said hierarchical porous material is composed of primary pore aggregates, the primary pore aggregates get together and formed the secondary pore aggregates, then the secondary pore aggregates connect to each other formed the hierarchical porous material; there are primary pores on said primary pore aggregates wherein the diameter of primary pore is 5-500 nm; there are secondary pores on said secondary pore aggregates wherein the diameter of secondary pore is 1-5 μm. Compared with existing technology, said hierarchical porous materials of this invention has apparent advantages of large surface area, high usage of precious metal and so on, which facilitating its mass transfer reaction when used as oxygen reduction reaction catalysts and other special applications.