Objective To Modify the permanent bilateral common carotid artery ( CCA) occlusion ( 2VO) for vascular dementia (VD) rats model，in order to increase the survival rate of model animals． Methods Vascular dementia was established by the modified 2VO method ( ligate unilateral CCA at first，ligate another one 7 days later) and the traditional 2VO method，respectively，and compared the differences of the two kind of methods in survival rates of rats， learning and memory ability and pathological morphology． Results One week after the operations，the survival rate of modified model group animal (86. 7% ) was obviously higher than traditional model group (40. 0% ，P ＜ 0. 05) ． Morris water maze test results showed that memory abilities in both modified and traditional model group were decreased obviously compared with the sham operation group ( P ＜ 0. 05 ) ，and there was no significant difference between modified model group and traditional model group． The neurons in hippocampus in modified and traditional model rats were all shown significant degeneration，necrosis and apoptosis． Conclusion The modified 2VO method is an ideal way to establish rat model of VD．