This　paper　aims　to　develop　a　multiscale　thermo-mechanical　coupling　model　across　from　meso-scale　to　macroscale　to　study　the　tensile　thermos-mechanical　behavior　of　fiber-reinforced　cementitious　composite　(FRCC)　on　the　base　of　thermodynamics.　In　meso-scale,　the　coupling　process　of　thermal　effect　and　the　development　law　of　a　single　crack　were　creatively　presented　and　formulated　in　energy　potential　function.　The　effects　of　fiber　dispersion　on　cracking　behavior　and　crack　strength　of　matrix　were　determined.　In　macro-scale,　the　multiple　-fine　-cracks　and　strain-hardening/softening　behavior　under　tension　were　defined　and　studied.　The　bridging　action　stress　of　fibers　is　calculated　by　considering　the　bonding　stress　in　the　interface　transition　zone　(ITZ).　The　model　can　be　upgraded　for　FRCC　materials　ranges　from　strain-hardening　cementitious　composite　(SHCC)　and　engineered　cementitious　composite　(ECC).　The　numerical　calculations　of　the　proposed　model　were　conducted　based　on　the　Fortran　program　for　validation.　The　residual　tensile　strength,　multiple　-fine　-cracks　and　strain-hardening/softening　behaviors　of　FRCC　were　predicted.　The　behaviors　of　FRCC　with　different　fiber　types　were　accurately　captured　in　a　range　of　temperature　from　20　degrees　C　to　600　degrees　C　through　the　comparative　study　with　six　groups　test　results　in　literatures.　A　sensibility　study　was　carried　out　to　analyze　the　impact　of　modelling　parameters　and　thermal　effect　on　the　strain-hardening/softening　behaviors　of　FRCC.