An improved algorithm is proposed for the shortage of Zhang refinement algorithm. First of all, the refinement template is designed according to the characteristics of the extracted skeleton, and the skeleton is refined and the skeleton connectivity is maintained and the single pixel is satisfied for subsequent processing. Secondly， using the pixels to find the skeleton of the branch point, the skeleton minus the branch points to form a number of non-connected areas. Different thresholds are selected according to the skeleton characteristics, and the connected branches which are smaller than the threshold will remove the skeleton glitches. This step effectively removes excess noise and glitches, optimizing the visual effect of the skeleton. The simulation results show that the improved skeleton is better than the Zhang refinement algorithm, not only in accordance with the threshold of choice to get rid of the length of the burr, and will not destroy the important structure of the skeleton.