The　volatility　and　uncertainty　of　high-penetration　renewable　energy　pose　significant　challenges　to　the　stability　of　the　power　system.　Current　research　often　fails　to　consider　the　insufficient　system　flexibility　during　real-time　scheduling.　To　address　this　issue,　this　paper　proposes　a　flexibility　scheduling　method　for　high-penetration　renewable　energy　power　systems　that　considers　flexibility　index　constraints.　Firstly,　a　quantification　method　for　flexibility　resources　and　demands　is　introduced.　Then,　considering　the　constraint　of　the　flexibility　margin　index,　optimization　scheduling　strategies　for　different　time　scales,　including　day-ahead　scheduling　and　intra-day　scheduling,　are　developed　with　the　objective　of　minimizing　total　operational　costs.　The　intra-day　optimization　is　divided　into　15　min　and　1　min　time　scales,　to　meet　the　flexibility　requirements　of　different　time　scales　in　the　power　system.　Finally,　through　simulation　studies,　the　proposed　strategy　is　validated　to　enhance　the　system＇s　flexibility　and　economic　performance.　The　daily　operating　costs　are　reduced　by　3.1%,　and　the　wind　curtailment　rate　is　reduced　by　4.7%.　The　proposed　strategy　not　only　considers　the　economic　efficiency　of　day-ahead　scheduling　but　also　ensures　a　sufficient　margin　to　cope　with　the　uncertainty　of　intra-day　renewable　energy　fluctuations.