Vascular dementia (VD) models were made first by repeating cerebral ischemia-reperfusion and followed by treating with estrogen. Learning-memory ability was measured by Morris water maze. Concentration of Ca2+ in hippocampus was determined by Fura-2/AM fluorescence probe and the expression of Calbindin-D28K (CB) in hippocampal CA1 was tested by immunohistochemistry. Learning-memory ability was improved in E group rats; Concentration of Ca2+ in hippocampus was decreased in E group rats. The expression of CB was less in E group rats. It implies that estrogen could improve learning-memory ability in VD rats, which may be associated with suppressing intracellular Ca2+ overload and increasing the expression of CB in hippocampus.