These　years　have　witnessed　the　increasing　popularity　of　global　energy　internet,　which　plays　a　significant　role　of　the　energy　revolution.　There　are　various　forms　of　energy　utilized　in　the　global　energy　internet,　such　as　electrical　power,　natural　gas,　and　heat,　and　the　integrated　dispatch　of　them　is　of　great　importance.　This　paper　proposes　a　model　of　joint　power-gas-heat　economic　dispatch　for　global　energy　internet,　which　applies　Alternating　Direction　Method　of　Multipliers　(ADMM)　to　realize　decentralization.　Heat　storage　devices　and　gas　contracts　are　considered　in　the　model,　which　corresponds　to　combined　heat　and　power　(CHP)　and　gas-fired　units.　Renewable　energy　sources　including　wind　power　and　photovoltaic　power　are　also　taken　into　account　to　make　the　formulation　more　realistic.　Case　studies　of　energy　internet　in　Northeast　Asia　are　performed　to　verify　the　effectiveness　of　decentralized　method　and　for　further　analysis.