Efficient　upconversion　Yb3+　and　Tm3+,　codoped　beta-NaYF4　is　firstly　synthesized　via　a　novel　and　rapid　microwave　hydrothermal　process.　The　as-prepared　sample　is　characterized　by　X-ray　diffraction　(XRD).　scanning　electron　microscopy　(SEM)　and　transmission　electron　microscopy　(TEM).　The　sample　shows　a　microtube　morphology,　which　may　be　formed　by　the　curliness　of　flakes.　It　is　found　that　NaYF4:Yb3+,　Tm3+　microtubes　can　be　synthesized　using　microwave　hydrothermal　method　in　a　much　shorter　reaction　time　compared　with　conventional　hydrothermal　method,　and　the　upconversion　fluorescent　intensity　is　also　greatly　enhanced　under　976　nm　laser　excitation.　The　energy　transfer　upconversion　mechanisms　and　the　possible　reason　for　the　enhancement　of　the　fluorescent　intensity　are　also　proposed.　(C)　2009　Elsevier　B.V.　All　rights　reserved.