This paper focuses on the calibration of the quadrupole of CSNS about determination of the center of the devices, analyzes the standard deviation values of magnetic center and rotation center obtained by the magnetic measuring platform, and the one of rotation center and mechanical center after the calibration of each magnet twice. The results show that the standard deviation of magnetic center and rotation center of the quadrupole obtained by the magnetic measuring platform is 0.1 mm, the repeatability accuracy after the calibration of the rotation center and the mechanical center of the CSNS quadrupole twice is within 0.03 mm, and the standard value of the deviation between the rotation and the mechanical center is 0.1 mm. Therefore, if the magnet center calibration cannot be carried out for similar devices of the same accuracy, the calibration based on rotation center instead of mechanical center, with deviation correction of rotation center and magnetic center, can meet the accuracy requirements of the current equipment alignment. This study provides important reference and guidance for the calibration of similar devices in the future.