In　this　work,　an　auto-identify　sensor　was　constructed　for　rapid　and　high-precision　detection　of　L-histidine.　The　proposed　strategy　is　based　on　the　auto-identify　algorithm　and　the　aggregation　of　alkynyl　and　azide　functionalized　gold　nanoparticles　induced　by　the　Cu+　catalyzed　azides　and　alkynes　cycloaddition　(CuAAC)　reaction.　Specially,　the　color　of　scattering　light　spots　for　the　aggregated　gold　nanoparticle　(AuNPs)　caused　by　CuAAC　reaction　was　quite　different　from　that　of　the　monomers.　However,　L-histidine　can　bind　to　Cu2+　and　inhibits　the　production　of　Cu+,　hence　preventing　the　aggregation　of　AuNPs.　Therefore,　there　is　a　distinct　change　of　color　as　the　addition　of　L-histidine　under　dark-field　microscopy.　Then,　L-histidine　can　be　quantitatively　detected　by　combining　the　color　change　with　the　Meanshift　algorithm　accurately　and　automatically.　Such　proposed　method　has　been　successfully　applied　for　the　detection　of　L-histidine　in　serum　sample　with　satisfying　result.　©　2021　Elsevier　B.V.