(2-Hydroxybenzylidene)-1-(quinolin-2-yl)-9H-pyrido-［3,4-b］ indole-3-carbohydrazide(QCS) was synthesized by a series of reactions with L-tryptophan methyl ester hydrochloride and 2-quinolinecarboxaldehyde as raw material. The structure of QCS was characterized by 1H NMR,13C NMR and ESI-MS. The probe QCS has a specific response to Al3+,and the limit of detection was 4.40×10-9 mol/L. QCS showed a good linearity in the concentration range of 9-100 μmol/L with a correlation coefficient(r2) of 0.999 1. In a mixed system of ethanol-water(9∶1,by volume),the binding ratio of QCS and Al3+ was 1∶1,and the complexing constant was proved to be(2.91±0.22)×103(mol/L)-1 in the fluorescence titration spectra. Furthermore,the fluorescent intensity of QCS-Al3+ maintained stable in the pH 5.0-8.0,which satisfied the requirements for detection on environmental water samples and living cells.