A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the formation of a complex between aluminium and N-((2-hydroxynaphthalen-1-yl)methylene) acetylhydrazide (HNMA). The fluorescence of the complex is monitored at an emission wavelength of 450 nm with excitation at 385 nm. Optimum complex formation occurred in Tris buffer at pH 6.0. Under the optimum conditions, linear calibration curves were obtained from 50 to 800 ppb. The detection limit was 9.2 ppb (ng mL −1). The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 2.5%. The effects of surfactants and interference from other ions were studied. The method was successfully applied for the determination of aluminium ions in water samples.