OBJECTIVE： To investigate the effects of memantine hydrochloride on cognitive function， cerebral hemodynamics and oxidative stress level in patients with vascular dementia （VD）. METHODS： A total of 70 VD patients in the Third Affiliated Hospital of Xinxiang Medical College from Feb. 2013 to Feb. 2015 were divided into control group （36 cases） and observation group （34 cases） aoccording to random number table. Observation group was given Memantine hydrochloride tablets orally with initial dose of 5 mg/d， qd， increasing by 5 mg/week gradually， maintaining at 20 mg/d， qd， at 4th week. Control group was given Piracetam tablets 0.8 g orally， tid. A treatment course of 2 groups lasted for 4 weeks， and both were treated for 6 courses. Clinical efficacies as well as MoCA scores， ADL scores， systolic peak velocity （Vmax）， diastolic peak velocity （Vmin）， pulsatility index （PI）， resistance index （RI） and breath holding index （BHI） of middle cerebral artery， the levels of MDA， SOD and Hcy were observed in 2 groups. The occurrence of ADR was recorded. RESULTS： Four， two patients withdrew from the study in control and observation group， respectively， and 32 patients in each group completed the study. The total response rate of observation group was 87.50％， which was significantly higher than 65.63％ of control group， with statistical significance （P＜0.05）.  Before treatment， there was no statistical significance in above indexes between 2 groups （P＞0.05）. After treatment， MoCA， ADL scores and SOD levels of 2 groups were increased significantly， while MDA and Hcy levels were decreased significantly； Vmax and BHI of observation group were increased significantly， and above indexes of observation group was significantly better than those of control group， with statistical significance （P＜0.05）. There was no statistical significance in Vmin， PI or RI between 2 groups before and after treatment， and Vmax or BHI of control group before and after treatment （P＞0.05）. ADRs of 2 groups were mild， and there was no statistical significance in the incidence of ADR between 2 groups （P＞0.05）. CONCLUSIONS： Memantine hydrochloride in the treatment of VD patients can improve the cerebral hemodynamics， reduce oxidative stress and improve cognitive function with good safety.