Objective:To study the effect of compatibility with Fructus Evodiae on intestinal absorption of alkaloids in Rhizoma Coptidis and its mechanism in rats.Method: In situ single-pass perfused rat intestinal model was used and the concentrations of berberine and palmatine were determined by HPLC.The drug absorption rate constant（Ka） and apparent absorption coefficient（Papp） were tested to evaluate the effect of compatibility with verapamil or Fructus Evodiae on their absorption.Result: Rhizoma Coptidis extractive and Fructus Evodiae extractive（6∶12） can significantly enhance Ka and Papp of berberine and palmatine.Two alkaloids in Rhizoma Coptidis and Fructus Evodiae extractive（6∶12） promoted their intestine absorption.When the compatible proportion was 6∶1

the absorption of berberine decreased

and the absorption of palmatine increased.Verapamil had a promoting effect on the absorption of berberine and palmatine.Conclusion: Fructus Evodiae extractive can promote the intestine absorption of berberine and palmatine

and the mechanism may be related to its inhibition of P-glycoprotein activity.