Abstract: Objective To study inhibitive effect of dihydroartemisinin(DHA)on proliferation of glioma C6 cells and to explore the mechanism of the effect.Methods C6 cells were cultured;the viability of the cells was detected with 3-(4,5-dimethylthiazol-2-yl)-2,5 phenyltetrazolium bromide(MTT)assay;the apoptotic rate of the cells was determined with annexin V/propidium iodide(V/PI)assay;the secretions of cyclin D1,bax,and caspase-3 proteins were detected with enzyme-linked immunosorbent assay(ELISA);the expressions of Bax and Bcl-2 proteins were examined with Western blot.Results DHA could significantly inhibit the proliferation of glioma C6 cells and the inhibition was the most obvious at 48 hours of DHA treatment.The viabilities of glioma C6 cells treated with 0.05,0.50,5.00 and 50.00μmol/L DHA for 48 hours were 83.96±1.08%,74.04±3.54%,68.70±9.20%,and 57.25±7.01%,respectively,with signifi-cant decreases compared to that of the control group(100.00±1.07%)(all P<0.01).Compared with the control group,the glioma C6 cells treated with 50.00μmol/L DHA showed a significantly increased apoptotic rate(25.98±3.95% vs.2.32±0.78%,P<0.01)),decreased expressions of cyclin D1 and Bcl-2 protein,and increased expressions of Bax and caspase-3 protein and Bax/Bcl-2 ratio.Conclusion Dihydroartemisinin could inhibit the growth of glioma cells through down-regulating the expression of cyclin D1 protein and up-regulating the expression of Bax/bcl-2,and the activated expression of caspase-3 protein.