In　this　paper,　the　economy　of　supercritical　compressed　air　energy　system　is　evaluated　by　using　thermaleconomic　method.　Electricity　price　of　input　system　to　evaluate　selects　by　the　beijing　municipal　market　price　for　peak　and　valley,　and　uses　Engineering　Equation　Solver　software　to　simulate.　The　results　show　that　the　electricity　price　of　output　is　0.5153　RMB/kW-h,　while　electricity　price　of　input　system　is　0.3148　RMB/kW-h　by　35　kV　valley　market　price,　there　is　obvious　economic　advantages　compared　to　the　peak　market　price.　This　system　has　no　CO2　and　other　greenhouse　gas　emission　comparing　with　the　compressed　air　energy　storage　system;　it　can　also　reach　the　purpose　of　regulating　network　load　and　improve　renewable　energy　power　system　efficiency,　so　it　has　significant　environmental　and　economic　advantages.　©　2011　IEEE.