Abstract: The complicated degree of structures and stability of coal seam is the main factor impacting the basic engineering lines layout.The Yangchangwan mine-field of Lingwu coal field,Lingxia was divided into several blocks of identical characters and assigned individually according to identification principles of structure and coal seam,assignment regularity as well as complicated degree of structure and stability of coal seam.The analysis re-sults showed that the mean structural index of main coal seams in this mine field is 0.29 and mean index of main minable coal seams is 0.7,which indicated that the coal seam structure is simplified and coal seams are stable.De-termination of complicated degree of coal seam structure and stability of mine-field by accurate data has a distinct influence on choosing line distance of the fundamental prospecting project.