The liver is an important organ in the lipid metabolism

excessive lipid accumulation in the liver induces the production of reactive oxygen species

leading to endoplasmic reticulum stress

mitochondrial dysfunction and lipid toxicity

which is closely related to non-alcoholic fatty liver disease（NAFLD）. NAFLD is not only associated with liver disease and death

but also closely related to type2 diabetes

atherosclerotic cardiocerebral vascular disease and extrahepatic malignant tumor. Recent studies have found that osteoporosis

bone density has certain correlation with NAFLD;some factors of bone metabolism are abnormal in different stages of NAFLD. In this paper

we will review the relationship between these factors（osteopontin

osteoprotegerin and bone morphogenetic protein

bone sclerosis and periosteal protein protein）and NAFLD.