In　order　to　investigate　the　nonlinear　mechanical　performance　of　prestressed　steel-concrete　composite　beams　under　positive　or　negative　moment　action,　systematical　experiments　up　to　13　prestressed　steel-concrete　composite　beams　are　carried　out.　Meanwhile　ABAQUS　program　is　adopted　to　simulate　static　behaviors　through　all　the　loading　range,　taking　into　account　material　nonlinearity,　geometrical　nonlinearity　and　the　interface　mechanical　characteristic　between　concrete　slab　and　steel　beam.　The　ultimate　flexural　strength,　ductility　of　composite　beams　are　predicted　and　analyzed　by　the　program　with　the　parameters　such　as　prestressing　force,　tendon　configuration,　shear　connection　degree　and　so　on.　It　shows　that　the　results　are　valuable　for　elastic-plastic　research　and　design　of　prestressed　steel-concrete　composite　beam.