Abstract: OBJECTIVE To study the absorption of astragaloside Ⅳ in the small intestine before and after the combination application of borneol. METHODS The changes of absorption kinetics of astragaloside Ⅳ inoculated with borneol were studied by in situ intestinal perfusion in rats. RESULTS There was no significant difference in the absorption kinetics parameters of astragaloside Ⅳ in the concentration range of 5~20 mg·kg^-1. There was also no significant difference in the kinetics parameters between astragaloside Ⅳ and astragaloside Ⅳ combined with 2.5 mg·kg^-1 borneol. While there was significant difference of absorption kinetics before and after being combined with 5 mg·kg^-1 and 10 mg·kg^-1 borneol(P<0.01). But there was no significant difference in the kinetic parameters between 5 mg·kg^-1 and 10 mg·kg^-1borneol group. CONCLUSION Borneol can promote the absorption of astragaloside Ⅳ in the small intestine in a certain dose range. It can be used in combination with astragaloside Ⅳ to improve the bioavailability.