The invention discloses a multi-cathode-compartment denitrifying phosphorus removal electrogenesis device by an activated sludge process, and belongs to the technical field of sludge treatment. The electrogenesis device comprises an anaerobic pool, a primary settling tank, an aerobiotic pool, a secondary sedimentation tank, an oxygen deficit pool and a final sedimentation tank, wherein the anaerobic pool is used as an anode compartment of a microbial fuel cell; the aerobiotic pool, the secondary sedimentation tank, the oxygen deficit pool and the final sedimentation tank are used as a cathode compartment of the microbial fuel cell and arranged around four sides of the anaerobic pool; the anode compartment and the cathode compartment are externally connected with resistors, and four pool walls of the anaerobic pool are equipped with proton exchange membranes. The anaerobic pool and the aerobiotic pool, the secondary sedimentation tank, the oxygen deficit pool and the final sedimentation tank are separated by the proton exchange membranes, and the proton exchange membranes can be freely opened and closed by a baffle. The primary settling tank is connected with the oxygen deficit pool through a surpass sludge pipeline, and the aerobiotic pool and the secondary sedimentation tank, the final sedimentation tank and the anaerobic pool are connected through backflow sludge pipelines; a water outlet pipeline and a sludge discharge opening are arranged on the final sediment tank; when the sludge is treated, power energy is generated. The multi-cathode-compartment denitrifying phosphorus removal electrogenesis device can effectively reduce the concentration of COD, TP and TN in sewage, and generate stable voltage value by widely using an electron acceptor.