Abstract: An UPLC-QTRAP-MS/MS analytical method for six blood components (rhein, aloeemodin, sinapic acid, liquiritin, isoliquiritin apioside, and wogonoside) in Daxiefei Decoction was established and applied to the pharmacokinetic study in normal and chronic obstructive pulmonary disease (COPD) model rats to reveal their absorption kinetics characteristics and elimination rules in vivo, in order to provide a scientific basis for the clinical application and further development of Daxiefei Decoction. The plasma concentrations of each substance at different time points were determined by ultra-performance liquid chromatography-triple quadrupole-linear ion trap mass spectrometry (UPLC-QTRAP-MS/MS), and the pharmacokinetic parameters of each component were calculated by pharmacokinetic software DAS 2.0. The results showed that the linear relationship between the six components was good in their respective ranges, and the methodological investigation met the requirements. The pharmacokinetic parameters of six components, such as peak concentration (C_max), peak time (t_max), half-life (t_1/2), area under the plasma concentration-time curve (AUC_0-t), were successfully calculated by using the pharmacokinetic software DAS 2.0 non-compartmental model. There were significant differences in the pharmacokinetic characteristics of the active ingredient group between the normal group and the model group, suggesting that the body was in different physiological states, and the change of the body state would have a certain impact on the absorption and elimination of the active ingredient of Daxiefei Decoction. The experiment was approved by the Laboratory Animal Ethics Committee of Nanjing University of Chinese Medicine (No. 202406A085).