Objective：To investigate the correlation between fat, muscle and bone and fall in elderly patients with chronic diseases, and to take measures to prevent the occurrence of fall, than to readuce the poor prognosis and improve the quality of life.Methods:A retrospective study of 128 patients with chronic diseases over 60 years old who were hospitalized in the Department of Geriatrics, Suzhou Ninth Hospital affiliated to Soochow University..The height, weight, body mass index (BMI) were measured, and the demographic data, conditions of chronic diseases were asked, and biochemical indexes such as blood routine, glucose, albumin and blood lipids were collected. Dual Energy X-ray (DXA) was used to measure fat mass, muscle mass and bone mineral mass in extremities and torso, and waist-hip ratio, fat mass index and ASMI were calculated. SPSS 22.0 software was used for analysis.Results: 1) The differences in age, body weight, BMI, total number of lymphocytes, activity of daily living(ADL), morse fall score, waist-to-hip ratio, fat mass index, limb and trunk fat and muscle mass between the decreased?muscle mass group and the normal muscle mass group were statistically significant (P < 0.05).2) According to the ASMI quartile，all the patients were divided into four groups. Comparative analysis of four groups showed that in addition to age, weight, BMI, the total number of lymphocytes, ADL, morse fall score, waist-to-hip ratio, BMI, limbs and body fat, muscle mass index, hemoglobin, limbs and trunk bone mineral content among the four groups were also statistically significant (P < 0.05).3) Pearson correlation analysis showed that fall was positively correlated with age (r =0.508, P < 0.05),and was negative correlation with body weight, BMI, hemoglobin, albumin, ADL, abdominal, hip, trunk and whole body fat mass, waist-hip ratio, fat mass index, lower limb muscle mass, ASMI and trunk bone mineral content (r = -0.28~-0.19, P < 0.05).Conclusion:The changes of body composition including decreased muscle mass and increased fat mass of elderly chronic disease patients will increase the risk of falling with aging. Therefore, it is necessary to take measures to improve the fat, muscle, bone mineral content and nutritional status of elderly chronic disease inpatients, so as to reduce the risk of falling and it’s complications and promote healthy ageing.