Abstract: The present invention belongs to the technical field of petrochemical engineering, and relates to a method for continuous post-treatment of benzotriazole (abbreviated as BTA) synthetic fluid. In particular, the present invention relates to a method for synthesizing BTA, including subjecting the BTA synthetic fluid to post-treatment steps of continuous acidification, water washing, extraction, back-extraction, dehydration, and distillation and the like. The method utilizes the difference in solubility of the BTA in water under different pHs to achieve separation by extraction without consuming a large amount of evaporation energy. The present invention is easy to operate, has little environmental pollution, high economic efficiency and low energy consumption, and is easily industrialized.