SrTiO3　(STO)　thin　film　was　coated　on　the　cladding　of　a　fiber　Bragg　grating　(FBG)　by　pulsed　laser　deposition,　and　the　associated　temperature　sensing　properties　were　tested.　The　surface　of　the　FBG　coating　was　smooth,　uniform,　compact　and　without　obvious　defects;　the　structure　and　properties　of　the　FBG　were　well　protected.　Temperature　sensing　results　showed　that　the　sensitivity　of　the　STO　coated　FBG　was　about　9.97　pm　degrees　C-1,　which　is　about　28%　higher　than　that　of　the　bare　FBG　(7.8　pm　degrees　C-1)　before　coating.　In　order　to　further　study　the　thermal　sensing　properties　of　the　FBG,　a　concatenated　optical　path,　two　optical　paths　based　on　a　Michelson　interferometer　and　a　Sagnac　interferometer,　were　constructed　by　using　STO　coated　FBG　and　another　bare　FBG　as　the　sensitivity　results　9.0　pm　degrees　C-1,　10.5　pm　degrees　C-1　and　11.4　pm　degrees　C-1,　respectively.　Among　them,　the　fiber　sensor　based　on　the　Sagnac　interferometer　was　more　sensitive,　which　was　increased　by　46.2%.　Moreover,　the　interference　optical　path　has　the　advantages　of　simple　structure　and　good　practicality.