Key　nodes　play　a　vital　role　in　the　transportation　network　by　significantly　influencing　its　structure,　function,　and　reliability.　Their　failure　can　severely　limit　the　transportation　efficiency　and　passenger　flow　of　urban　agglomerations.　To　address　the　limitations　of　single　traffic　mode　and　incomplete　evaluation　indexes,　this　paper　proposes　a　weighted　multi-layer　network　node　importance　evaluation　method　that　considers　node　connectivity,　diverse　transportation　modes,　and　service　capabilities　(CDSM).　Firstly,　based　on　the　long-distance　bus　stations,　railway　stations,　and　airports　in　the　Beijing-Tianjin-Hebei　urban　agglomeration　(BTHUA),　the　comprehensive　transportation　network　(CTN)　is　constructed.　Secondly,　evaluation　indexes　including　degree,　closeness,　capacity,　and　grade　are　selected　to　build　the　weighted　model　and　obtain　the　comprehensive　importance　of　nodes.　Finally,　the　effectiveness　of　the　method　is　verified　by　the　susceptible-infected-recovered　model.　The　results　show　that:　1)　The　CTN　in　this　paper　can　reflect　real　traffic　links　among　different　transportation　modes　in　urban　agglomerations.　2)　When　the　top　5　and　top　10　key　nodes　identified　by　the　CDSM　are　used　as　initial　infected　nodes,　the　infection　and　propagation　rate　of　the　CTN　are　higher　than　traditional　methods　such　as　the　using　degree,　betweenness,　closeness,　and　k-shell.　Specifically,　the　infection　rate　is　2.8%　and　3.2%　higher　than　the　average　of　these　methods,　and　the　propagation　rate　is　7　and　2.3　time　steps　faster　respectively.　3)　The　more　key　nodes　initially　infected,　the　higher　the　infection　and　propagation　rate　of　the　CTN.　4)　The　key　nodes　identified　in　this　paper　include　important　transportation　hubs　of　BTHUA,　aligned　with　reality.