Circulating water supply system

The invention provides a circulating water supply system. The circulating water supply system comprises a cylinder body, a first piston, a piston rod and an anti-deposition mechanism; a water inlet and a water outflowing channel are formed in the upper end of the cylinder body; the first piston is movably disposed in the cylinder body, and the first piston is in seal contact with the inner wall ofthe cylinder body; the upper end of the piston rod is connected to the lower end of the first piston, and the piston rod drives the first piston to slide up and down in the cylinder body; and the anti-deposition mechanism is disposed in the cylinder body and used for preventing impurities in water from depositing in the cylinder body. By means of the circulating water supply system provided by the invention, the impurities in a water body can be effectively prevented from depositing in the cylinder body, and influence, on normal operation of the circulating water supply system, of depositionof the impurities is avoid