A noval azo-based fluorescent probe (NA-M), derived from 6-amino-m-cresol and 1-naphthol, was successfully synthesized and characterized. NA-M had a significant enhancement of fluorescence with Al₃₊ ^{at 590 nm in} MeOH/HEPES (9/1, v/v, pH=7.4) solution, and displayed high specificity, strong anti-interference and good sensitivity (8.4×10_-7 ^M). The 1:2 binding stoichiometry between Al₃₊ ^and probe had been established from Job’s plot. Meanwhile, the complex NA-M+Al₃₊ showed high selectivity and good anti-interference ability to F_- by quenching the fluorescence, and the detection limit of complex NA-M+Al₃₊ ^to F_- ^{could reach} to 9.5×10_-7 M. Eventually, probe NA-M and its complex NA-M+Al₃₊ had also been successfully applied to detect Al₃₊ ^and F_- ⁱⁿ actual samples, respectively.