Abstract：Objective：To observe the clinical effect of the theory of toxin damaging the brain collateral on the treatment of vascular dementia(VD) based on western medicine treatment. Methods： 100 VD patients with the syndrome of kidney essence depletion and phlegm and blood stasis obstructing the collaterals were randomly divided into the control group and the observation group， 50 cases in each group. Both groups were treated with Donepezil tablets and Nimodipine tablets orally，and risk factors including blood glucose，lipid and blood pressure were strictly controlled. The observation group was additionally treated with Kaixin powder and Tongqiao Huoxue tang. Both groups were treated for 16 weeks. Before and after 16 weeks of treatment， the scores of Mini- Mental State Examination(MMSE)， Alzheimer's Disease- 8(AD8)， Activity of Daily Living Scale(ADL) and Chinese medicine syndrome were evaluated. The clinical effect was compared between the two groups after treatment. Results： After treatment， the clinical effect in the observation group was better than that in the control group(P＜0.05). The MMSE scores in the two groups were increased when compared with those before treament (P＜ 0.01)， and the scores of AD8， ADL and Chinese medicine syndrome were decreased(P＜0.01). The MMSE score in the observation group was higher than that in the control group(P＜0.01)，and the scores of AD8，ADL and Chinese medicine syndrome were lower than those in the control group(P＜0.01). Conclusion：Based on conventional treatment with western medicine，the additional application of Kaixin powder and Tongqiao Huoxue tang in treating VD of the type of kidney essence depletion and phlegm and blood stasis obstructing the collaterals， can improve the patients' cognitive ability， behavioral ability and memory ability，reduce clinical symptoms and improve the ability of daily life as well as clinical effect.