As a unified graphics standard of power systems in the future, SVG( Scalable Vector Graphics) is widely used in Web. This paper integrates SVG and Surfer technologies and uses SVG as the basis of power system visualization to implement the visualization for nodal voltage of power systems in the platform of VB. Practical application shows that in the distribution power network monitoring systems using this technology to draw a large number of contour lines is convenient, fast and accurate. It has a good application prospects.