The　foundation　pit　area　of　Kunming　International　Comprehensive　Transportation　Hub　is　56,800　m2,　and　the　excavation　depth　ranges　from　18　m　to　25　m.　Because　the　surrounding　environment　is　very　complex,　the　foundation　pit　is　supported　by　an　underground　continuous　wall　and　three　layers　of　internal　support　system　with　seven　rings.　The　force　of　this　internal　support　system　is　coupled　integrally,　and　the　number　of　rings　is　the　highest　in　the　world　at　present.　In　this　work,　a　finite　element　model　considering　the　interaction　between　soil　and　the　retaining　structure　is　established.　The　Hardening　Soil　model　with　small　strain　stiffness　is　used　to　simulate　and　analyze　the　whole　excavation　process　of　the　foundation　pit.　Considering　the　ultra-large　plane　size　of　the　foundation　pit,　we　cannot　ignore　the　temperature　effect,　so　the　deformation　of　the　underground　continuous　wall　and　the　force　of　the　internal　support　system　under　seasonal　temperature　variation　are　investigated.　By　comparing　numerical　simulation　results　with　field　measurements,　the　deformation　of　the　ultra-large　seven-ring　internal　support　system,　the　deformation　of　the　surrounding　soil,　and　the　axial　force　of　the　supports　are　analyzed.　The　results　show　that　the　finite　element　simulation　agrees　well　with　the　measured　data.　This　work　provides　a　reliable　method　for　analyzing　ultra-large　deep　foundation　pits.