Abstract: Aiming to the low-efficiency problem of graph outline extraction caused by repetitive search and selection interruption of paths, the graphic elements' priority characteristics are defined, including the region priority, neighborhood priority, boundary priority and routing priority.Furthermore, the priority characteristics are respectively set by the limit value method, the eigenvalue comparison method, the extreme point method and the dynamic optimization method.The extraction process and path selection are controlled through matching graphic elements' priority characteristics, and an efficient algorithm of graph outline extraction is presented.Finally, the practical application validated the effectiveness and stability of the proposed algorithm.