In　order　to　figure　out　flexural　performance　of　reinforced　concrete　girders　strengthened　with　prestressed　CFRP　plates,　test　and　nonlinear　finite　element　analysis　on　six　reinforced　concrete　(RC)　girders　and　four　partially　prestressed　concrete　(PPC)　girders　strengthened　with　prestressed　CFRP　plates　were　carried　out　under　static　load.　The　influences　of　the　damage　degrees,　initial　prestresses　of　CFRP　plates　and　effective　prestresses　of　girders　on　the　flexural　performance　of　these　strengthened　girders　were　investigated.　The　results　show　that　the　formation　and　development　of　cracks　can　be　restrained　effectively　using　prestressed　CFRP　strengthening　methodology,　the　crack　width　and　deflection　of　components　can　be　reduced,　and　the　flexural　capacities　of　the　strengthened　RC&PPC　girders　can　be　improved　significantly.　The　greater　the　pre-strengthening　damage　degree,　the　earlier　the　concrete　stripping,　the　larger　the　decrease　of　ultimate　flexural　capacity　as　well.　At　the　failure　stage,　the　stripping　of　the　CFRP　plates　always　occurs　firstly　and　then　the　rupture.　The　flexural　performance　of　strengthened　RC&PPC　girders　can　be　predicted　by　the　nonlinear　finite　element　(FE)　model　before　the　stripping　of　CFRP　plates,　and　the　calculated　results　show　good　agreement　with　experimental　results.　In　practical　engineering,　the　reasonable　initial　prestressing　degree　in　CFRP　plates　should　be　about　0.5.