Objective: To explore the safety concentration of berberine in vitro and its insulin resistance (IR) on adipocyte. Method: The 3T3-L1 preadipocytes were taken into blank control and different concentrations of berberine (0.001~10 μmol·L-1)groups. The A value of each group was measured by MTT method after 48 hours. Mature 3T3-L1 preadipocytes were divided into control and IR model group. The cell culture medium and glucose content were detected after the model group cells were inducted by 10 μmol·L-1 insulin for 24 h and 48 h. Glucose content in the culture medium of the IR model were detected after intervention for 24 h and 48 h. Result: Compared with the control group

the A values of three 0.01-1 μmol·L-1 berberrine groups increased and 10 μmol·L-1 group increased and decreased significantly (P<0.05

P<0.01). Compared with the normal group

the glucose content of culture medium induced by Ins for 24 h and 48 h increased and decreased significantly (P<0.01). Compared with the model group

the glucose content in culture medium of 0.01-1 μmol·L-1 berberine groups after 24 h and 0.0001-1 μmol·L-1 berberine groups after 48 h decreased significantly (P<0.01). Conclusion: The safety concentration of berberine in vitro is low

and the low concentration of berberine in vivo has a significant anti-IR activity.