Distribution　network　possesses　many　nodes　and　its　topology　is　complex.　In　the　implementation　of　distribution　automation　(DA),　it　needs　to　know　the　position　of　each　node　and　the　interconnection　among　the　nodes.　In　topological　model　of　distribution　network　not　only　the　adjacency　among　the　nodes　should　be　described,　but　also　the　path　among　the　nodes.　On　the　basis　of　the　features　of　the　topological　structure　of　distribution　network,　two　equivalent　decoupling　methods　are　presented,　i.e.,　the　border　connected　method　and　the　border　disconnected　method,　thus,　the　single　branches　of　which　number　is　equal　to　that　of　the　nodes　are　obtained.　The　decoupling　results　by　the　two　methods　reflect　the　connection　of　the　nodes　in　distribution　network　and　the　topological　layers　of　distribution　network.