In order to solve the problems of poor antinoise performance and low precision existing in the current rapid calibration method for monocular camera of laser cutting vision system, an improved camera selfcalibration method based on nine dots was proposed. The theory of the algorithm was analyzed and verified by experiment.The improved nine dots calibration algorithm was compared with the existing monocular camera fast calibration algorithm by experiment. The results show that the improved nine dot calibration algorithm has better antinoise performance and higher accuracy than the existing monocular camera fast calibration algorithm.