Traditional laser beam width measurement methods usually adopt optical instruments with diffraction, interference and other methods, which are specific constraints in accuracy and speed. In contrast, there are rarely using image processing methods. The laser beam width acquisition method is obtained by laser beam integration model. The intensity distribution function of laser is obtained by Sobel operator and Gaussian filter, and the pixel width is calculated on the xaxis and yaxis by Hough fitting circle integration area. The experimental results show that the image processing algorithm is practical and reliable for measurement of laser beam width, and the measurement effect is intuitive and convenient compared with the traditional measurement methods.