The present invention discloses a porous material and preparation method thereof. The material includes a material body. The body is composed of pore cavities classified into different levels according to the pore size of the material and cavity walls surrounding to form the pore cavities. The lower-level pore cavities are arranged on the cavity walls of the upper-level pore cavities formed by surrounding a three-dimensional space. All the pore cavities are interconnected. The preparation method is: mixing the raw powders with a pore-forming agent for the smallest-level pore cavities of the porous material to formulate a slurry , uniformly filling the slurry into the polymer material support to form a green body and get dried and smashed to obtain mixed grains, uniformly mixing the mixed grains with the pore-forming agent for upper-level pore cavities which are greater than the smallest-level pore cavities of the porous material to make a compact green body, and then performing vacuum sintering. Perform the conventional follow-up treatment in accordance with the raw materials process of the porous material. The porous material has good connectivity and uniform properties. Each level of the porous material has its own physicochemical properties and can fully satisfy the demands of various functions. The porous material can be used as a biomaterial, a separation material and the like, and the preparation method is simple and easy to implement.
