Seal plug is a newtype part which is used to seal auxiliary holes. However, domestic seal plugs have many deficiencies.A new kind of sealplugperformance testing equipment was designed for seal plug performance testing and further optimization design. For the purpose of the research, the hydraulic control system was discussed, and the accuracy of the system was optimized by using the least square method and difference method. The design method for this equipment can be extended to the design of other test equipments, which has great practical significance.