This experiment's with aim was to study the pharmacokinetics of asperosaponin VI and its three metabolites (cauloside A, HN saponin F and hederagenin) via a sensitive high performance liquid chromatography connected with electrospray ionization triple quadrupole mass spectrum (HPLC-ESI-MS/MS). Chromatographic separation was achieved on a reverse phase C18 column with a gradient mobile phase of CH3CN-water with 0.1 % HCOOH at a flow rate of 0.3 mL/min. Sample analysis was simultaneously performed with a multiple reaction monitoring mode using target determination ions at m/z 927.5 → 603.4 for asperosaponin VI, m/z 811.1 → 603.4 for cauloside A, m/z 649.4 → 603.4 for HN saponin F, m/z 71.4 → 393.3 for hederagenin and m/z 307.0 → 161.1 for warfarin as the internal standard. The calibration curve was linear at the range of 0.25-500 ng/mL, and the lower limit of quantification was 0.25 ng/mL for each compound. While the precisely intra-assay and inter-assay variabilities were <9.5 and 7.8 %, respectively; accuracy was determined at the concentrations of 5, 25, 100 ng/mL for all the analytes with the relative standard deviation (%) no more than 15.0 %. Consequently, the validated method could be successfully and precisely applied to the pharmacokinetic study of asperosaponin VI and its metabolites. As a result, the pharmacokinetic parameters of cauloside A, HN saponin F and hederagenin such as T max were obtained at 9.33 ± 2.49, 7.33 ± 0.47 and 12.33 ± 2.36 h, respectively.