Objective To study the expression of NF-κB and CyclinD1 in human ovarian cancer Caov-3 cells after using proteasome inhibitor MG132.Methods Cell culture and immunohistochemical assessment were performed for alterations in expression of NF-κB and CyclinD1.Results The expression level of NF-κB and CyclinD1 decreased in Caov-3 cells after being treated with MG132 for 24 hours.The differences were statistically significant(P0.01).Conclusion MG132 could significantly induce the apoptosis of Caov-3 cells.The part of anti-tumor mechanism of MG132 suppresses tumor growth and induces apoptosis by inhibiting expression of NF-κB and CyclinD1.