A simple procedure to perform for the determination of amoxicillin is presented, based on reaction with 1-[(quinolin-6-ylcarbamoyl)oxy]pyrrolidine-2,5-dione (AccQ-Fluor) in borate buffer medium at pH of 7.4. The resulting amoxicillin+AccQ-Fluor derivative was determined by reversed-phase chromatography with combined fluorescence (λex=245 nm/λem=368 nm) and UV detection (λ=245 nm) for control. The calibration graph was linear (r=0.9992 ) over the range 5.0-30 μg/mL. The method was applied to the determination of amoxicillin in pharmaceutical formulations with acceptable precision and accuracy.