The oxidative degradation of benzothiazole (BTH) in a single-chamber electro-assisted microbial reactor was investigated. The effects of applied voltage and COD/BTH ratio on the performance of degrading benzothiazole were studied. The research showed that BTH was oxidized to 2-hydroxy-benzothiazole (OHBT), then thiazole ring scission, and BTH translated into 2-methylsulfonylaniline eventually. The degrading of benzothiazole was in conformity with the pseudo first-order kinetic model, and the pseudo first-order kinetic constant can be increased by raising the applied voltage and co-metabolism. When the applied voltage was 0.7 V and COD/BTH ratio was 30, the degradation rate was 96% in 48 h, achieving the detoxification of BTH, and that is advantageous to the biochemical treatment.