To avoid the disadvantage of the present algorithms of corner detection, which can only detect the locations of corners in images, but cannot pick up the angles of corners, an algorithm for picking up angles of corners in images is proposed based on Radon transform. The algorithm utilized SUSAN to detect corners, caught the neighborhood image of corners which were detected, and then judged whether the corner was measurable or not. If the corner was measurable, there was a grader mapping to each pixel. At last, Radon transform was used to extract edge lines of corners, and the geometry relation of coordinate was applied to pick up angles of corners. Radon transform could not detect original location of a line, which caused the defects of two values when one corner was picked up. To solve this problem, the same nucleus was used to angles picked-up through the idea of USAN for reference. Experiment results show the algorithm is effective.