In　this　work,　sulfhydryl　functionalized　carbon　dots　(SH-CDs)　were　synthesized　for　the　first　time　by　a　two-step　hydrothermal　method.　The　sulfhydryl　group　in　SH-CDs　can　be　converted　efficiently　and　reversibly　in　a　few　minutes　under　redox　conditions.　On　this　basis,　ochratoxin　A　(OTA)　induced　hybrid　chain　reaction　amplification　and　alkaline　phosphatase　enzymatic　hydrolysis　to　produce　ascorbic　acid　(AA).　AA　reduced　the　aggregated　SH-CDs,　thereby　realizing　the　dual-mode　rapid　quantitative　analysis　of　the　OTA　concentration　by　measuring　the　changes　in　the　fluorescence　intensity　and　absorbance　of　the　SH-CDs　solution.　The　proposed　sensor　has　a　good　linear　relationship　with　the　OTA　concentration　in　the　range　of　2.0-5.0　nM,　and　the　lowest　detection　limit　is　2.0　nM.　Additionally,　the　visual　color　change　of　the　solution　can　improve　the　simplicity　and　accuracy　of　semi　-quantitative　detection　of　OTA　with　the　naked　eye.　In　short,　this　method　has　the　advantages　of　rapidity,　sensi-tivity,　reversibility　and　visualization.