The invention discloses a valve plate of a butterfly valve based on reduction of cavitation damage. A taper angle alpha of a rigid sealing surface is greater than 45 degrees and less than 60 degrees, an assembling hole at the middle of the valve plate is biased to a fluid inlet from a central position of the valve plate, the valve plate, which is close to one side of the fluid inlet, is a plate surface, and the other side is a guide taper surface, three groups of comb teeth, which are uniformly arranged in a radial direction at radiuses of R1, R2 and R3 and a ratio of R1 to R2 to R3 of 11: 19: 27, are arranged on the plate surface and the guide taper surface, each group of the comb teeth can be inclined to the central position, a slant angle omega is greater than 60 degrees and less than 66 degrees, the comb teeth are cones provided with arcs at the top, the cone angles are 5-7 degrees, and the comb teeth between the groups are staggered at an equal distance. The valve plate, provided by the invention, has a function of a single-eccentric center butterfly valve, when the valve is opened or closed, a rubber valve seat is irregularly gradually compacted by the periphery of the valve plate from each position so as to generate a magnitude of interference, a hermetical pressure is realized, and the good sealing property is realized. In addition, fluid flows through the comb teeth on the valve plate, so that the pressure difference of the front and the back of the valve is reduced, and the valve cavitation phenomenon is reduced.