The　study　of　today＇s　Cyber-Physical　System　(CPS)　has　been　an　important　research　area.　Internet　Data　Centers　(IDCs)　are　energy　consuming　CPSs　that　support　the　reliable　operations　of　many　important　online　services.　Along　with　the　increasing　Internet　services　and　cloud　computing　in　recent　years,　the　power　usage　associated　with　IDC　operations　had　been　surging　significantly.　Such　mass　power　consumption　has　brought　extremely　heavy　burden　on　IDC　operators.　Recently　there　are　extensive　research　on　power　management　for　IDCs.　While　most　work　only　consider　about　dynamical　optimization　of　IDC　under　electricity　markets,　the　reaction　of　IDC　toward　electricity　market　has　been　overlooked.　Due　to　the　fact　that　IDCs　are　usually　large-volume　users　in　the　electricity　market,　they　might　have　market　power　to　affect　the　electricity　price.　In　this　paper,　we　study　how　to　address　the　challenge　of　interactions　between　IDC　operation　and　electricity　market　price.　To　this　end,　we　propose　a　supply　function　to　model　the　market　power　of　IDC　and　formulate　a　total　electricity　cost　minimization　problem　as　a　non-linear　programming.　In　order　to　design　efficient　solution　method,　we　transform　the　optimization　problem　to　a　quadratic　programming.　Extensive　performance　evaluations　demonstrate　that　the　proposed　method　can　effectively　minimize　the　total　electricity　cost　of　IDCs　by　adaptively　handling　the　interaction　between　IDCs　and　smart　grid.