A sensitive and selective spectrofluorimetric method was developed for the determination of alfuzosin in pharmaceutical preparations and urine. The method is based on reaction of alfuzosin with 1-dimethylaminonaphthalene-5-sulphonyl (dansyl) chloride in carbonate buffer of pH 9.7 to yield a highly fluorescent derivative that is measured at 516 nm after excitation at 405 nm. The developed method was validated according to the criteria for analytical method, showing good performances in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, recovery and robustness. The fluorescence intensity versus concentration plot was rectilinear over the range of 25 to 500 ng/mL. The LOD and LOQ were found to be 8 and 25 ng/mL, respectively. The method was successfully applied to the determination of alfuzosin in pharmaceutical preparations and urine.