ing at the laser stripe images with the local bending obtained by the laser triangulation measurement system, a method based on the Fourier-polar transformation algorithm to measure the local bending is proposed. Through the computing, the normal direction of laser stripe is obtained. The gray projection of the spatial-domain image along the normal direction is conducted, and the magnitude of the local bending is obtained directly. This method has advantages of a simple computing process and high immunity to random noises and the non-uniform intensity distribution of laser stripe. The theoretical analysis and experimental test verify the effectiveness of this method.