Ecological　network　analysis　is　an　important　tool　for　urban　energy　metabolism　research,　but　it　does　not　consider　the　dynamic　and　synergy　features　of　the　system,　which　constraints　its　application　in　urban　transition　studies.　In　this　paper,　we　modified　the　ecological　network　analysis　method　to　identify　the　key　factors　that　dominate　the　evolution　of　the　urban　energy　metabolism.　Focusing　on　the　dynamic　and　synergy　characteristics　of　the　system,　we　observed　the　changes　of　direct　and　indirect　energy　consumption　flows　and　combined　with　Haken　model　to　determine　the　dominant　factors　of　the　metabolic　processes.　A　case　study　on　Beijing　was　conducted　to　diagnose　the　key　flows　that　impact　the　evolution　of　Beijing＇s　energy　metabolic　system　during　2010-2015.　Results　suggest　that　despite　the　decline　in　Beijing＇s　coal　consumptions,　the　direct　and　indirect　parts　have　different　tendency　among　sectors.　During　the　research　period,　the　pathway　＂coal　to　industry＂　displays　dominant　effects　on　the　evolution　of　Beijing＇s　energy　metabolic　system.