A　novel　fluorescence　immunoassay　has　been　developed　for　alpha-fetoprotein　(AFP)　detection　based　on　copper　ions　(Cu2+)　regulated　formation　of　quantum　dots　in　situ.　In　place　of　traditionally　used　fluorophore　or　enzyme　for　signal　amplification,　CuO　nanoparticles　(NPs)　were　used　as　signal　amplifier　to　enhance　the　detection　sensitivity.　In　the　presence　of　AFP,　CuO　NPs-labeled　antibody　can　be　specifically　captured　through　the　sandwich-type　immunoreaction.　By　the　use　of　L-cysteine　(Cys)　as　stabilizer,　aqueous　fluorescent　CdS　quantum　dots　(QDs)　can　be　formed　by　a　facile　synthesis　method.　After　acid　dissolution,　numerous　Cu2+　ions　were　released　from　the　CuO　NPs,　which　can　act　as　catalyst　to　catalyze　the　oxidization　of　Cys　and　thus　greatly　reduce　the　amount　of　CdS　QDs　formed.　The　fluorescence　intensity　showed　a　good　linear　relationship　with　the　AFP　concentration　in　the　range　from　1　to　80　ng/mL,　as　low　as　0.45　ng/mL　AFP　can　be　detected.　The　high　throughput,　disposability,　sensitivity　and　accuracy　of　the　proposed　fluorescence　immunoassay　showed　good　applicability　in　clinical　diagnosis.　(C)　2017　Elsevier　B.V.　All　rights　reserved.