Zhi Ling Tang (ZLT [symbol: see text], a TCM prescription designed for replenishing essence, supplementing marrow, invigorating qi, warming yang, removing blood stasis and phlegm, tonifying the brain, and invigorating mental activity) was used in 32 cases of senile dementia (SD). After treatment, the levels of serum cholesterol (Tch), triglyceride (TG), and plasma lipid peroxides (LPO) were lowered; the content of high density lipoprotein (HDL) and the activity of superoxide dismutase (SOD) in RBC significantly elevated, the cerebral blood flow was increased; latent period of P300 and P3 waves was shortened while the amplitude of P3 elevated; and topographic electroencephalogram, revised Hasegawa dementia scales (HDS) scores (P < 0.05-0.01) and clinical symptoms were improved. The total effective rate was 81.3%, indicating that ZLT exhibits relatively good therapeutic effects for treating senile dementia.