A rapid, specific, and sensitive ultra fast liquid chromatographic method for simultaneous determination of aspartame (ASP), acesulfame-K (ACE-K), caffeine (CAF) and sodium benzoate (SB) has been developed and validated. The chromatographic separation was achieved on a Shim-pack XR-ODS column within a run time of 3 min using acetonitrilepH 3 phosphate buffer (20 : 80, v/v) as the mobile phase at a flow rate 1.5 mL/min and the column temperature was set at 40 degrees C. The elaborated method was validated according to the International Conference on Harmonization quidelines. Linear calibration graphs were in the ranges of 120280 mu g/mL for ASP and ACE-K, 90210 mu g/mL for CAF and 60140 mu g/mL for SB. The limits of detection were 1.6, 4.3, 3.9 and 4.1 mu g/mL for ASP, ACE-K, CAF and SB, respectively. The limits of quantitation were 5.2, 14.4, 12.9 and 13.7 mu g/mL for ASP, ACE-K, CAF and SB, respectively. The intra- and inter-day precisions were less than 2%. The recoveries for the analytes were between 98.8799.73% and the precision values from 0.06 to 0.35.