Abstract: A method of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the simultaneous determination of 16 perfluoroalkylated substances (PFASs) in oral liquid products. The residual of perfluoroalkylated substances in samples were extracted using methanol acidified with 2% hydrochloric acid solution as the extraction solvent, then enriched by N-propylethylenediamine (PSA) and PestiCarb (GCB) absorbent after adjusting extract's pH to neutral. Next, the compounds were eluted with 50 mmol/L triethylamine-methanol solution. At last, the exact was analyzed by HPLC-MS/MS in negative mode with multiple reaction monitoring (MRM). All the analyte were calibrated by the internal method. Good linearities were established for the 16 perfluoroalkylated substances in the range from 0.2 g/L to 20 g/L. For all of 16 perfluoroalkylated substances, the limit of detection is less than 0.15 g/L, while the limit of quantitation is less than 0.43 g/L. The average recoveries of 16 perfluoroalkylated substances are between 80.8% and 119% in the spiking levels of 0.5, 1.0, 2.0 and 5.0 g/L. The relative standard deviation (RSD) of 16 perfluoroalkylated substances is less than 10.5%. The method is simple, rapid and sensitive, which suits for determination of 16 perfluoroalkylated substances in oral liquid samples.