Abstract: CaMnO₃ is an important N-type thermoelectric material. (Ca_1-x Y_x)MnO₃(x =0, 0.03, 0.05, 0.07, 0.09)thermoelectric samples were synthesized based on solid state reaction method, and thermoelectric properties were measured with self-made equipment. The results show that Y³⁺ doping can improve the thermoelectric properties effectively. As for Ca_0.91Y_0.09MnO₃, during the test temperature of high side reaches 880K, the resistivity, Seebeck coefficient and maximum output power are equal to 74 mΩ · m, -112 μV/K, 68 mW, respectively.