Abstract: Objective To explore the effects of juglone on proliferation and apoptosis of human cervical cancer Caski cells.Methods Cultured Caski cells were incubated with 20, 40, 60, 80, and 100 μmol/L juglone for 24 hours and the untreated cells were used as the control.The proliferation of Caski cells was detected with 3-(4, 5)-dimethylthiahiazo-(-z-yl)-3, 5-diphenytetrazoliumromide(MTT) assay.Optical microscope was used to observe morphological changes of the cells.Nuclear fragmentation and apoptotic body were observed with Hoechst 33258 staining, and the cell apoptosis was detected with flow cytometry(FCM).Results MTT results showed that the growth of Caski cell was greatly inhibited by 40, 60, 80, and 100 μmol/L juglone, with the optical density(OD) values of 0.65±0.11, 0.53±0.14, 0.40±0.11, and 0.31±0.05, respectively(P<0.05 for all) and a dose-dependent trend compared with that of the control group.Hoechst 33258 staining results showed typical morphological changes in Caski cells cultured with 40 μmol/L juglone for 12 hours.Flow cytometry results showed that the early apoptosis ratio of Caski cells was 2.86±0.47%, but the ratio of the cells treated with 40 μmol/L juglone was increased to 15.47±2.56%(P<0.05).Conclusion Juglone significantly inhibits the proliferation and induces the apoptosis of Caski cells in vitro.