OBJECTIVE In this study, RNA interference was used to evaluate the effects of HMGB1 expression on cell cycle and proliferation of the human cervical cancer cell line HeLa. METHODS We had previously constructed and screened effective eukaryotic expression vectors carrying PGCsi3.0-1/HMGB1 siRNA and PGCsi3.0-3/HMGB1 siRNA, then the vectors were transfected into HeLa cells. The expression of HMGB1 before and after transfection in HeLa cells were detected by RT-PCR and West blot. The cell viability and proliferating activity was tested by Trypan blue dye test and MTT, and the cell cycle was determined by flow cytometry. RESULTS The introduction of PGCsi3.0-1/HMGB1 siRNA and PGCsi3.0-3/HMGB1 siRNA inhibited the expression of HMGB1 mRNA and protein efficiently and specifically, there was a significant difference between the siRNA groups and the control groups (P < 0.05). The proliferation speed of PGCsi3.0-1 group and PGC si3.0-3 group were obviously slower than those of PGCsi3.0-Neg group and non-transfected group. Flow cytometry showed that the content of DNA in G2 phase in PGCsi3.0-1 group and PGCsi3.0-3 group were obviously more than those in PGCsi3.0-Neg group and non-transfected group, but the content in S phase was less (P < 0.01). The progression of cell cycle was arrested from G2 to S phase. CONCLUSION PGCsi3.0-1/HMGB1 siRNA and PGCsi3.0-3/HMGB1 siRNA could specially suppress the expression of HMGB1 gene, inhibit the proliferation speed of HeLa cells effectively, and arrest the progression of cell cycle from G2 to S phase. RNAi provides a new approach to the bio-therapy of cervical cancer.