The invention discloses a preparation method of a metal organic polymer material. The preparation method comprises the following steps: in an electrolytic cell, using ionic liquid as electrolyte, using a metal electrode or a titanium-based oxide electrode as an anode, using a titanium plate as a cathode, turning on a power supply, controlling the temperature and current density to carry out electric synthesis, carrying out solid-liquid separation, washing the product through a solvent, and then, washing the product through chloroform, and drying the product to obtain the metal organic polymer material; and finally, removing organic ligands, metal salt ions and solvent molecules out of pores of the synthesized metal organic polymer material and from surfaces of the pores to prepare the metal organic polymer material. The method of the invention is carried out under normal temperature and normal pressure, thereby having the advantages of mild reaction conditions, simple process, easiness for controlling the reaction, no secondary pollution, etc and is clean, sanitary and friendly to the environment.