An optical nanosensor based Mn doped ZnS quantum dots（QDs）was synthesized using 6-hydroxynictinic acid（6-HNA） as template via surface molecular imprinting sol-gel method.Fourier transform infrared spectroscopic（FT-IR） spectra and scanning electron microscopic（SEM） images showed that the imprinted polymer was successfully grafted onto MIP-QDs.Adsorption tests revealed that the affinity and selectivity of MIP-QDs for 6-HNA were significantly higher than its analogues nicotinic acid and coumalic acid.Under the optimized conditions,a phosphorescent sensor for detecting 6-HNA was constructed.The linear range for detection of 6-HNA was in the range of 3.4-67.0 μmol/L with a detection limit of 1.03 μmol/L and a correlation coefficient（r2） of 0.996 5.Recoveries of 91.0%-103.9% and relative standard deviations less than 4.5% were achieved in real samples,which were in good agreement with that of the high performance liquid chromatographic（HPLC） method（P>0.05）.The proposed method had good veracity and feasibility.