Abstract: In order to improve corner detection probability and obtain satisfactory marking quality in laser marking systems, a corner detection algorithm based on slope difference was proposed and theoretical analysis and experimental verification were carried out. After calculating the slopes of adjacent points, the corner points were picked up in terms of slopes difference. The simulation results show that the proposed algorithm can achieve accurate corner points with less computation complexity compared with the traditional algorithms. This algorithm can solve inflection point processing problems in the traditional marking systems, save storage space and reduce the computational complexity in the process of extracting image inflection points.