The invention relates to a desulphurization pump with a combined impeller rotor. The desulphurization pump comprises the combined impeller rotor, a pump case, a pump inlet part, a pump outlet part anda pump back cover plate, wherein the pump inlet part, the pump outlet part and the pump back cover plate are installed on the pump case to form a pump cavity for containing the combined impeller rotor in an enclosure manner; the combined impeller rotor comprises an impeller body installed on a pump shaft, the impeller body comprises a metal hub lining and a nonmetal blade lining body with which the peripheral surface of the metal hub lining is wrapped in a compression-molding manner, and the nonmetal blade lining body is made from an ultrahigh molecular weight polyethylene material. Accordingto the desulphurization pump with the combined impeller rotor, the deadweight of the impeller body is reduced, and the material cost is saved; in addition, the strength of the impeller body is also guaranteed while it is avoided that the impeller rotor is too thick; the impeller body is resistant to wear and corrosion, and a vibration value of the pump can be reduced; meanwhile, processing is easy, the cost is low, and the running efficiency of the pump is greatly improved.