To address the inaccurate measurement of cylindrical surface defects caused by perspective projection in machine vision systems， an image correction method to resolve cylindrical surface perspective projection distortion is proposed. In this method， the image area of the cylinder is first extracted. Then， the transverse and axial directions are determined. On the basis of the perspective projection characteristics of the cylindrical surface， the distortion is divided into axial and transverse deformation. The imaging parameters and cylindrical radius are utilized to establish the corresponding relationship between the coordinates of the original image and the those of the corrected image. The perspective projection distortion is corrected by pixel mapping and nearest neighbor interpolation. The experimental results demonstrate that the proposed method affords a good correction effect on images of different-diameter cylindrical surfaces. Both near-large and far-small perspective deformation and oblique projection deformation are eliminated in the corrected images. For the checkerboard simulation correction， the measurement error for the side length of the six cylindrical checkerboard squares decreases from a highest of 14.9% before correction to 1.2% after correction. In a scratch measurement， the maximum errors in the original image of two cylinders of different diameters are 78.0% and 61.8%. After correction using the proposed method， the maximum errors are only 5.9% and 5.5%， respectively. The remarkable correction effect verifies the effectiveness of the method.