This work is devoted to the study of a two-stage cold hollow magnetron cathode for an electric thruster, including those operating on chemically active working substances. A solution to the problem of vulnerability of hot cathodes-neutralizer of electric thrusters in the presence of chemically active working substances by using a magnetron cathode is proposed. To reduce the energy cost of an electron and increase the efficiency of the magnetron cathode, it is proposed to use an additional ionization stage. Experimental results of a study of the operation of a two-stage cathode are presented. A reduction in the energy cost of an electron in a two-stage cathode by 1.6 times compared to a single-stage version was obtained. The prospects of using the multistage concept of the cathode on the presented simplified mathematical model are discussed. A forecast is given for reducing the energy cost of an electron in a multistage cathode to 120–140 eV.