The present invention relates to a water quality management system for managing the quality of water in a water tank by using the power that is generated by using the solar energy, wherein a motor driving of a motor unit is controlled on the basis of a state of the water quality or water amount measured by a sensor unit, a state of the power that is generated by an energy generation unit, and a state of charge of a battery unit, such that the power usage efficiency could be improved, and the water quality and the water feeding and drainage in a farm, etc could optimally be managed.
