Abstract: The proposed algorithm generates the accurate distance from boundary （DFB） field for the 3D tubular object,then the maxima-l spanning tree （MST） is constructed based on the DFB field.By Dijkstra algorithm the centerline of the tubular object is extracted from the MST tree.The experimental results show that an accurate DFB field can indeed make the extracted centerline much more accurate,and the fast implementation method improves the computational efficiency of the proposed algorithm.In addition,the extracted centerline of the tubular object can be directly used in the system of virtual endoscopy.