Before conducting measurement work on a coordinate measuring machine, it is necessary to calibrate the probe, which is a very important work step before conducting measurement. There are two main reasons for correcting the probe: to obtain the compensation diameter of the ruby ball of the probe and the relationship between different probe positions and a probe position. During the measurement of a coordinate measuring machine, the gemstone ball of the measuring needle is used to contact the measuring part of the measured part. At this time, the probe (sensor) sends a touch signal. After the signal enters the counting system, the raster counter at this moment is locked and sent to the computer. The measuring software in operation receives a point represented by the X, Y, and Z coordinates. This coordinate point can be understood as the coordinate of the center of the probe gemstone ball, which differs by one gemstone ball radius from the contact point between the probe gemstone ball and the workpiece that we really need. In order to accurately calculate the contact point coordinates we need, the half/diameter of the probe gemstone ball is obtained through probe calibration. In actual measurement work, parts cannot be moved or turned over at will. In order to facilitate measurement, it is necessary to select measuring needles (star, column, needle) with different probe positions, lengths, and shapes based on the actual situation. In order to directly calculate the elements measured by these different probe positions and different probes, it is necessary to measure the relationship between them and convert them during calculation. Therefore, it is necessary to calibrate the probe.