To extract the laser stripe center of a rough metal surface accurately, an extraction method based on light cutting was presented. Firstly,the noise source of an image was analyzed by the image morphology, then the noise was converted into a granular shape while the continuous feature of an effective laser-stripe was still kept through an image enhancement processing.The noise and the laser-stripe were segmented by counting the connected areas of the image, and the denoised binary laser-stripe image was taken as a mask to be multiplied by the original image to recover the gray scale information of the laser-stripe image. Finally, the denoised laser-stripe center of the gray scale image was extracted with a barycenter method. Experimental results show that the laser-stripe centers extracted with the proposed method all locate in the laser-stripe region. The average error of the center extraction of a much-noised straight line laser-stripe by this method can reach 0.337 5 pixels.