A porous metal material. The material is a multi-grade porous metal material. Grading is performed according to material pore diameters, and there are at least two grades. The pore diameter of a minimum-grade porous metal material is less than 1 micrometer, the elastic modulus of the minimum-grade porous metal material is less than 80 GPa, and the porosity is not less than 48%. A preparation method for the porous metal material comprises: mixing raw material powder for preparing the porous metal material and a pore-forming agent for preparing a minimum-grade pore cavity to prepare slurry; uniformly filling the slurry into a high polymer material support, to form a body, and drying and crushing the body to obtain mixed particles; uniformly mixing the mixed particles with a pore-forming agent for preparing a pore cavity that is bigger than the minimum-grade pore cavity, to prepare a compact body; and performing vacuum sintering, and performing regular subsequent treatment according to the raw material process. The material has multi-grade elastic modulus to meet different use requirements, has desirable connectivity, and is particularly suitable to serve as a tissue regeneration material. The preparation method is simple and is easy to implement.