The invention provides a preparation method of a porous heterogeneous bone meal repair material. The method comprises the following steps: (1) preparing cancellous bone of mammals into powder, carrying out washing by adopting water, carrying out drying, carrying out soaking by adopting hydrogen peroxide solution and sodium hydroxide solution respectively for preliminarily removing organic matters,carrying out complete washing by adopting water, and carrying out drying; (2) placing the cancellous bone with the organic matters preliminarily removed and an alkaline solution in a pressure-bearingclosed container, carrying out heating, carrying out thermal insulation, carrying out washing by adopting water, and carrying out drying; (3) placing the cancellous bone and distilled water in the pressure-bearing closed container, carrying out heating, carrying out thermal insulation, carrying out washing by adopting water, and carrying out drying; and (4) carrying out calcining, and carrying out sterilization treatment. The invention further provides the porous heterogeneous bone meal repair material prepared by adopting the preparation method. With the preparation method provided by the invention, fat and protein which cause the immunizing antigen reaction can be completely removed under the relatively low temperature condition, during the treatment process, the pollution of poisonousand harmful organic solvents does not exist, and the treated heterogeneous bone material is in the slight crystallization structure, contains abundant bicarbonates, and can well promote the bone tissue regeneration.