A　sensitive　and　selective　fluorescent　sensor　for　flumioxazin　was　designed　based　on　the　formation　of　strong　fluorescence　compound　(1,2,3-triazole　compounds)　via　the　reaction　of　the　alkynyl　group　in　flumioxazin　with　3-azido-7-hydroxycoumarin,　a　weak-fluorescent　compound,　through　the　Cu+-catalysed　azidealkyne　cycloaddition　(CuAAC)　reaction.　The　fluorescence　increase　factor　(represented　by　F/F-0)　of　the　system　exhibited　a　good　linear　relationship　with　the　concentrations　of　flumioxazin　in　the　range　of　0.25-6.0　mu　g/L　with　a　detection　limit　of　0.18　mu　g/L　(S/N　=　3).　Also,　the　proposed　fluorescent　sensor　demonstrated　good　selectivity　for　flumioxazin　assay　even　in　the　presence　of　high　concentration　of　other　pesticides.　Based　on　such　high　sensitivity　and　selectivity,　the　proposed　fluorescent　sensor　has　been　applied　to　test　the　flumioxazin　residue　in　some　vegetable　and　water　samples　with　satisfied　results.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.