Abstract: Objective: To develop detection method for the simultaneous screening and confirmation of 27 illegally added in slimming health food using high performance liquid chromatography-tandem mass spectrometry ( HPLC-MS/MS) .Methods: The chemical drugs were separated on an Agilent Eclipse Plus C₁₈ chromatographic column ( 2.1 mm × 100 mm, 1.8 μm) with acetonitrile and aqueous solution of 10 mmol/L ammonium acetate ( adjust to p H4.0 with formic acid) as mobile phase under gradient elution at a flow rate of 0.2 m L/min.The 27 illegally added in slimming health food were conducted qualitatively and quantitatively analysis by tandem mass spectrometry under multiple reaction monitoring ( MRM) mode.Results: The method was linear with correlation coefficients ( R²) which were not less than 0.99, and the precision expressed as relative standard deviations ( RSDs) were not more than 8.0%.The recoveries of 27 drugs illegally added in slimming health food at different spiked concentrations ranged from 74.5% to 106.7%.The limits of detection ( LODs) were in the range of 0.2 ~ 204.2 ng/g.Conclusion: This method is rapid, accurate and sensitive with a high degree of separation, and can be used for the detection of the 27 illegally added chemicals in slimming health foods.