Abstract: Laneway is one of the principal parts in geological virtual scenes.A hierarchical modeling method for plane connected laneway entity based on media curves was proposed.Node-path graph according to the broken up curves generated by intersection points of media curves was constructed.All closed loops were picked up through outer path tracing prior principle.The cross-section data of media curves were obtained,and a series of hierarchical contours were built,which compose the hierarchical contours of the laneway after offset calculation and connection of boundary path.Finally,triangular grids of laneway were generated by 3D objects reconstruction of adjacent contours and triangulation for both roof contour and bottom contour.The results show that topology of the vertexes and paths was used to reduce calculation burden,simplify implementati