Objective: To investigate the absorption mechanism of dauricine based on Caco-2 cell line.Method: Bidirectional transport of dauricine in Caco-2 cell model was used;apparent permeability coefficients（Papp）

efflux ratio（ER） and accumulation transport amount were calculated;the effect of drug concentration

pH gradient and EGTA on the bidirectional transport of dauricine were studied.Result: At high

middle and low concentrations the efflux ratio（ER） was 1.11

4.49

7.24 respectively

so there was significant polar phenomenon for transport of dauricine;at apical lateral when pH was 7.4 and 6.5

ER were 3.95 and 9.38 respectively

so pH gradient could reduce the absorption of dauricine;chelator EGTA couldn’t affect the Papp

ER and accumulation transport amount of dauricine.Conclusion: The active transport was included in the absorption mechanism of dauricine

pH gradient could increase the polar phenomenon

transmembrane pathway is the main absorption route for dauricine.