Supercapacitors have the characteristics of high specific capacitance, long cycle life and green pollution-free, and their excellent electrochemical performance has attracted much attention. In this paper, NiMoO_4/g-C₃N₄ composite powder was hydrothermally synthesized, and the composite powder was coated on foamed nickel to prepare NiMoO₄/g-C₃N₄ electrode material. The results show that the morphology of NiMoO₄/g-C₃N₄ powder is mainly NiMoO₄ nanorods and g-C₃N₄ clumps, and NiMoO₄ nanorods are grown on g-C₃N₄ nanosheets.The electrochemical performance test results show that adding 30at% g-C₃N₄ to NiMoO₄ can reduce the equivalent series resistance and diffusion impedance of the capacitor system, which is beneficial to the oxidation-reduction reaction. Compared with other electrode materials with g-C₃N₄ content, NiMoO₄/g-C₃N₄ electrode materials with a g-C₃N₄ content of 30at% have higher specific capacitance (584.3F/g) and better rate characteristics.