Abstract: This study was designed to develop a rapid quantitative detection strip for MC-LR（microcystin-LR）in water samples using the fluorescent nanosphere immunochromatograhic technology. Based on competitive mode，an immunochromatograhic strip system was developed for detecting MC-LR，and the reagent performance was evaluated for its sensitivity，accuracy，specificity and stability. Several parameters for preparing immunochromatograhic strip，i.e.，the concentration of artificial antigen on the test line，labeling rate of nanosphere and antibody，the concentration of nanospheres on the conjugate pad，were optimized. After the sample added for 15 min，the immunochromatographic assay was finished with a linear working range，0.195 μg/L of sensitivity，99.4% of recovery，below 10% of variable coefficient，little cross reaction with MC-LF，well consistency with commercial kits，and solid stability for 6 days at 37℃. In summary，this fluorescent nanosphere immunochromatographic strip is sensitive，stable，accurate，rapid，quantitative，and easy performed for MC-LR detection.

Key words: immunochromatographic, microcystin, nanosphere, fluorescence