Alzheimer's disease(AD),the most common progressive neurodegenerative disease in dementia,is also a special lipid disease.From the perspective of modern medicine,cholesterol homeostasis is an important risk factor for AD.Amyloid-beta plaque deposition,neurofibrillary tangles,and large amount of lipid granule accumulation are typical pathological features of AD.From the perspective of TCM,turbidity is the key to the pathogenesis of AD.Phlegm turbid,stasis turbid and turbid toxin are the concrete derivation of turbidity,which are the standard of AD.Cholesterol is the greasy lipid which is produced from of the essence of water and food,the disturbance of cholesterol homeostasis is a typical embodiment of the pathogenesis mechanism of endogenous turbidity.Regulating cholesterol homeostasis by traditional Chinese medicine may be a new direction for the treatment of AD in the future.Focusing on the modern research of cholesterol homeostasis,taking the theory of turbidity as the starting point,this paper analyzed the correlation between the connotation of turbidity theory and the imbalance of cholesterol homeostasis as well as the pathogenesis mechanism,and further elucidated the clinical application results in the treatment of AD from the aspects of phlegm turbid,stasis turbid and turbid toxin,so as to better guide clinical practice and scientific research.