Water-soluble CdSe quantum dots（QDs） were synthesized in aqueous solution with thioglycollic acid as stabilizer.By using CdSe QDs as fluorescent probe,based on the enhancement of the fluorescence intensity of CdSe QDs by glycyrrhizin（GL）,a simple,rapid and sensitive method for the determination of GL was proposed and validated.Forthermore,the possible mechanism of interaction between CdSe QDs and GL was discussed.Effects of experimental conditions were investigated.The optimal conditions were as follows:buffer:pH 7.4 Na2HPO4-NaH2PO4 solution,concentration of quantum dots:2.4×10-4 mol/L,reaction time:10 min.Under the optimal conditions,a good linearity was obtained between fluorescence intensity and GL concentration in the range of 5.0×10-9-1.0×10-7 g/L with a correlation coefficient of 0.998 0.The obtained linear regression equation was:IF/I0F=1.337+0.014ρ（10-9 g/L） and the limit of detection was 4.8×10-9 g/L.The proposed method was successfully applied in the determination of GL in actual samples,and the results were in good agreement with that of the national standard method in Chinese Pharmacopoeia.The study indicated that the combination of QDs and GL produced a nice labelling effect,and it would be of considerable significance to the further investigation of GL targeted carrier system.