The invention relates to a control method for using a scaling prevention solar centralized water supply system. The control method comprises the steps that a scaling prevention mode or a heating modeis operated; and when the temperature is higher than scaling temperature, hot water is in a flowing cooling state all the time, a water tank and a water pipe in contact with the hot water can achievea scaling prevention effect very well, and service life is prolonged. In addition, heat can be converted into electric power to be accumulated, power is supplied to a power using module, waste of water and energy is reduced, and resources are utilized reasonably.