The invention belongs to the technical field of rare metal refining, and in particular, relates to a method for preparing porous titanium powder. The technical problem to be solved of the invention is to provide a method for preparing porous titanium; and the method comprises the following steps: a titanium raw material is added in an electrolyte for electrolysis to obtain the porous titanium powder on a cathode; the electrolyte is a mixture of titanium halide and molten salt; the molten salt is at least one of an alkali metal halide or a rare earth metal halide; and in electrolysis, an anode adopts an inert material or a metal material with more positive potential compared with titanium, and the cathode adopts a metal material. The method can prepare the porous titanium powder.