Abstract: In the pseudo-random coded structured light system，the automatic corner detection method is proposed.First，the data cluster method is used to determine the correspondence between the camera image and the projector image，it solves the pattern codification；and then by the corner detection method，the coordinates of all the proper and non-redundant corners in the encoded image are given automatically，as well as the row and the column numbers of these corners.These provide the important data for the sub-pixel location of corners.The method is applied to the system that authors develop，experimental results demonstrate that this method is effective for solving the corner detection and correspondence problem in the course of projector calibration.