Herin, a Schiff base (L) based on 2‑hydroxy-1-naphthaldehyde and 3-amino-4-pyrazolecarboxylic acid ethyl ester was successfully designed, synthesized and characterized. Spectroscopic experiments demonstrated that L can selectively recognize Al3+ with fluorescence, exhibiting a detection limit (DL) of 4.2 × 10−8 mol/L, significantly lower than that of previously reported Schiff base fluorescent sensors. The Job's plot analysis demonstrated the 1:1 stoichiometry between the Al3+ and L, with bright blue fluorescence observed under 365 nm ultraviolet light irradiation. The recognition mechanism involves the coordination of Al3+ ions with two oxygen atoms originating from the carboxylate and phenol groups, as well as the nitrogen atom of the imine moiety in Schiff bases. Additionally, the interaction nature between L and Zebra fish DNA (zf-DNA) was found to be intercalation and minor groove based on both spectroscopic method and theoretical docking study. Furthermore, the main interaction force between L and DNA was hydrophobic with a spontaneous process based on the fluorescence spectra obtained at different temperatures, which can also be attributed to static quenching. Above all, this Schiff base could be used to detect Al3+ ions in the environmental system with high accuracy. This study is also expected to contribute to the understanding of the binding mode of this type of complex to DNA, proposing a novel approach for development and creation of versatile sensors, and investigating new anticancer agents, modifying or detecting bio-molecules.