To study the effect of Shenma Yizhi Decoction (SMYZD) on cognitive function and white matter lesions in VD rats.Methods:A total of 60 surgery modeled Wistar rats were randomly divided into Sham group, Model group, SMYZD-L group, SMYZD-M group, SMYZD-H group and Donepezil group.After 2 weeks administration of SMYZD, Morris water maze test was used to detect cognitive function of rats.Brain tissue LFB staining was used to observe loss of myelin sheath of the Corpus callosum and White matter damage scoring.Western blot was used to detect the expression of myelin basic protein (MBP).Results:Escape latency of rats in SMYZD-H group significantly shortened.Time spent in target quadrant significantly prolonged.Grading score of white matter damage significantly diminished, and MBP expression augmented.Conclusion:Shenma Yizhi Decoction could improve cognitive dysfunction and alleviate white matter damage of VD rats.