The invention discloses a water-cooling type valve plate of a hot-blast valve, wherein, a water-cooling pipeline is arranged in a valve plate body, and the water-cooling pipeline is a multi-layer circumferential water channel, and water channel clapboards are evenly disposed on each layer in the circumferential water channel for making the water flow around one direction; a water-cooling ring is arranged on the two side faces of the valve plate body near to the outside diameters, an annular cooling water channel is arranged in the water-cooling ring, and a water inlet and a water outlet are communicated with the water-cooling pipeline disposed in the valve plate body. Because the two sides of the valve plate body are respectively a non-sealed side and a sealed side, the non-sealed side is one side of the hot-blast valve facing the main hot-blast pipe and bearing big thermal load, cooling water can firstly enter the side of the valve plate for circulating cooling and then enter the sealed side of the valve plate for cooling, then the two side faces of the valve plate can be cooled orderly. Compared with the valve plate of the micro-water energy-saving hot-blast valve disclosed in CN1769501, the valve plate obviously improves the cooling effects at both sides and balances the heat at both sides, and synchronizes the service life, and the valve plate can bear rather big thermal shock and thermal fluctuation, and will not be damaged when being started frequently, thereby extending the service life of the whole hot-blast valve.