With the rapid development of aquaculture industry, more and more attention has been paid to the environmental problems caused by aquaculture tailwater. As an eco-friendly water treatment technique, electrocoagulation has attracted much attention due to simple operation, high efficiency of pollutant removal and small footprint. In this paper, the research progress of electrocoagulation technology, purification principle, influence factors and its application in aquaculture were discussed. In addition, the application of electrocoagulation technology in algae removal, turbidity and COD removal, nitrogen and phosphorus removal, sterilization and disinfection, and coupled application with other water treatment technologies, as well as the energy consumption calculation, hydrogen recovery and utilization and challenges of electrocoagulation technology were introduced. The energy consumption, energy recovery and the challenges faced by electrocoagulation technology in actual production were discussed. The electrocoagulation water treatment technology has a broad application prospect. With the continuous improvement of equipment and technology, its practical application in the treatment of aquaculture tailwater will continue to be expanded.