Abstract: A method for the simultaneous analysis of four sweeteners (acesulfame-K, sodium saccharin, sodium cyclamate and aspartame) and two antioxidants (tert-butylhydroquinone and butylated hydroxyanisole) by liquid chromatography-quadrupole time-of-flight mass spectrometry has been established. An extend-C₁₈ chromatographic column and ESI (-) were used, respectively. Six compounds were separated rapidly in 6 min with 1 mmol/L of ammonium acetate-acetonitrile as the mobile phase with gradient elution. Results showed that the limit of detection ranged from 0.250 0 to 5.000 ng/mL, and the relative standard deviation of day-to-day was less than 10.71% (n=3). This assay was suitable to liquid sample detection, with average recoveries in the range of 83.24%~118.3%. The proposed method with good accuracy and high sensitivity can be applied to the rapid analysis of sweeteners and antioxidants in food.