bjective To estabolish vascular dementia animal model with ligation of bilateral common carotid arteries, the volume of blood flow in various regions of rat brain was determined. Methods The changes in volume of flood flow in different brain regions were measured by laser Doppler blood flow monitor within 10 minutes after ligating the bilateral common carotid arteries of rats. Results The average of volume of brain blood flow decreased (lobus frontalis 67.83%; lobus parietalis 56.82%; lobus occipitalis 16.16%; basal nucleus of Meynert 51.21%; caudate putamen 41.18%; field CA1 of the Ammon's horn 51.83%; field CA2 of the Ammon's horn 41.21%) after the ligation. Conclusion The volume of blood flow in the brain regions closely related to the ability of learning and memory all declined significantly.