Purpose: To investigate the fundamental properties of a poorly absorbed drug, bergenin, and explore an effective way to enhance its oral absorption; Methods: The physicochemical properties were investigated.An in situ perfusion model was developed to assess and modulate the drugs absorption across the rat intestinal mucosa; Results: As a weak acid, bergenin has poor lipophilicify and water solubility.It is easily degraded in neutral and alkaline media.In the range of 70~140μg/ml, the drug shows passive absorption behavior.Lecithin, F-68,and sodium dodecyl sulfate (SDS) were found to be effective absorption promoters when Carbomer 934p (CP) was used as stabilizer;Conclusion: The results indicated the influencing factors for bergenins absorption and provided basic information to select suitable absorption enhancers.