In the repair of mechanical manufacturing and measuring instruments, high-precision grinding is an important process. When the surface roughness and flatness requirements are high, the dry grinding method (plate sanding with grit) can generally be used to meet the requirements. However, the sand pressing plate used in the dry grinding method is difficult to manufacture, the use time is short, and the cutting force is small, which satisfies In order to improve the grinding speed, I have studied and applied a method of processing wet high-precision planes in combination with wet research and dry research in order to improve the grinding speed. This method not only ensures the accuracy, but also greatly improves the work efficiency.