Abstract: A portion (1.000 0 g) of compound seasoning sample was extracted twice with mixed solvent of CH₃OH and H₂O (50+50) to transfer the analyte, advantame, from the sample into solution. 10 mL of the mixed solvent was used in each extraction, which was performed by swirling for 10 min and centrifuging for 5 min with high speed. Supernatants from the 2 extractions were collected and diluted to 25.0 mL with water. An aliquot of 1.0 mL of the solution was mixed by swirling for 1 min with 200 mg of C₁₈ and 100 mg of PSA in an EP tube and centrifuged for 2 min with high speed for purification. The supernatant was filtered through 0.22 μm filtering membrane and 5 μL of the filtrate was introduced into the instrument by using Agilent ZORBAX SB-C₁₈ column as stationary phase and using mixtures of 0.1% (φ) formic acid solution (A) and CH₃OH (B) mixed in various rations as mobile phases in the programed gradient elution. ESI with positive ion scanning mode and mode of MRM were adopted in MS/MS. Linearity range for advantame was found between 0.2 to 20 μg·L^-1, with detection limit (3S/N) of 2.0 μg·kg^-1. Using powdery and pasty seasoning samples as matrixes, tests for recovery and precision were made by standard addition method, giving values of recovery in the range of 89.3% to 98.5%, and values of RSDs (n=6) in the range of 1.8% to 3.8%.