Abstract: OBJECTIVE To study the effect of carboxylesterase inhibitor(tanshinoneⅡA) on pharmacokinetic characteristics physalin D in rats. METHODS Twelve SD rats were randomly divided into the control group and tanshinone Ⅱ A group, which was administrated respectively with normal saline and tanshinone ⅡA. After pretreated with tanshinoneⅡA (50 mg·kg^-1, qd) for 3 d, physalin D was given to the rats by intragastric administration. The plasma concentrations of physalin D were determined by HPLC-MS/MS. The main pharmacokinetic parameters were calculated by WinNonlin 6.3 software, pharmacokinetic parameters between two groups were then compared with t test by SPSS 11.0 software. RESULTS There had significant differences between the two groups in the main pharmacokinetic parameters of physalin D(P<0.05). AUC_{0-24 h} and C_max of oxymatrine D were significantly increased after continuous administration of tanshinone ⅡA for 3 d. CONCLUSION Ginsenone ⅡA can significantly influence the pharmacokinetic process of physalin D in rats.