The invention relates to a method for automatically purifying and recycling water discharged from a dry quenching water seal system. The water discharged from the dry quenching water seal system is collected and then fed into a purifying water tank for automatic purification treatment, and fed back to the dry quenching water seal system by means of a booster pump afterwards for cyclic utilization. The purifying water tank comprises a water tank, the booster pump, an electric water replenishing valve, and a water tank liquid level meter. The top of the water tank is sealed, and a water inlet pipe is arranged at one side of the water tank, while a water outlet pipe is arranged at the other side of the water tank. The interior of the water tank is sequentially divided into first, second, third and fourth areas by a first tank partition plate, a baffle plate, and a second tank partition plate along the water flow direction, and a folded line-shaped water flow channel is formed; a water replenishing pipe and an overflow pipe are also arranged at the same side to the water outlet pipe; the booster pump is arranged on the water outlet pipe; the electric water replenishing valve is arranged on the water replenishing pipe; the water level in the purifying water tank is monitored by the water tank liquid level meter. Interlocked control over the water tank liquid level meter, the booster pump and the electric water replenishing valve is achieved by means of a control system. The method for automatically purifying and recycling water discharged from the dry quenching water seal system is capable of realizing cyclic utilization of water discharged from a dry quenching process and achieving the purposes of energy conservation and emission reduction.