AIM: To investigate the effect of Tetrandrine (Tet) on proliferation of human pterygium fibroblasts (HPF) in vitro and to search for a new method to prevent the recurrence after pterygium surgery. METHODS: With different concentrations (0 to 160μmol/L) of Tet acting on HPF cultured in vitro , the impact was observed at 24, 48, 72 hours respectively after Tet intervention. The MTT method was used to assay the biologic activities of Tet and inhibitive rate of cell growth. The expression of proliferating cell nuclear antigen (PCNA) in each group was detected by immunohistochemistry before and after Tet intervention. RESULTS: With different concentrations of 20, 40, 80 and 160μmol/L and acting for 24 to 72 hours, Tet could inhibit the proliferation of HPF in a dose- and time-dependent manner (P <0.05). After the intervention of Tet, the expression of PCNA protein declined. When the concentration of Tet was in the range of 20 to 160μmol/L, it was able to inhibit the expression of PCNA in a concentration-dependent manner (P <0.05). CONCLUSION: Tet can significantly inhibit the proliferation of pterygium fibroblasts, and the inhibitive action is in a dose- and time-dependent manner within a certain range of concentration. But in high concentration (>160μmol/L), Tet will have cytotoxity.