Based on the image representation with polygons,a new approach to the SVG vectorization representation of raster images is proposed. First, the original raster image is segmented into a number of polygon areas based on color, and each polygon is combined by several equal size element blocks of the similar color. Then, the border vertex of the polygon is optimized. Finally, the SVG code is used to describe the raster image based on the shape and color of polygons. The approach that uses vector graphics to describe raster images proved to be good with a relatively small storage space, zooming without serrated edges, and little deformation.