In order to improve the performance of drum seal for hydraulic cylinder piston in pure water medium,taking the piston seal of ZY10000-20-40DB shield hydraulic support as the research object,a two-dimensional axisymmetric model of drum seal structure was established by using Ansys finite element software.The sealing performance and damage characteristics of the drum seal with different sealing groove structure size and sealing ring structure size were analyzed by orthogonal test method under the condition of piston inner stroke and outer stroke,and the drum seal structure was optimized.The results show that compared with the structural parameters of the sealing ring,the structural parameters of the sealing groove have little effect on the sealing performance,and the change of chamfer size in the groove does has no effect on the sealing performance.Excessive or too small size of the seal ring edge will cause stress concentration.The maximum von Mises stress and contact stress increase with the radius of convex arc outside the seal ring, and decrease with the radius of concave arc inside the seal ring.The maximum contact stress of the optimized drum seal increases by 18% to 20%,and the sealing performance is significantly improved.