Abstract: A chiral LC-MS/MS method for the simultaneous analysis of desvenlafaxine (DVS) enantiomers in human plasma was developed and applied to a pharmacokinetic study on 12 Chinese healthy volunteers. d₆-Desvenlafaxine was used as internal standard (IS). Chromatographic separation was performed on the Astec Chirobiotic^TM V chiral column (150 mm × 4.6 mm, 5 μm). The assay was linear over the concentration range of 0.500-150 ng·mL^-1 for both enantiomers (r² > 0.99). The method was successfully applied to a stereoselective pharmacokinetic study of 100 mg desvenlafaxine sustained release tablets on 12 Chinese healthy volunteers under fasting conditions. The results showed that the pharmacokinetic parameters were similar to both enantiomers in Chinese healthy volunteers. The AUC_0-t and C_max of the two enantiomers were about 1.5 times higher than those of blacks and whites reported in the literature.