Objective To investigate the prevalence of chronic diseases in the elderly inpatients in Beijing Friendship Hospital and its changes in recent 10 years. Methods Statistical data from the front page of medical records in 60630 elderly inpatients in our hospital from January 2008 to December 2017 were collected and analyzed for the prevalence of chronic diseases. At the same time, the comorbidity of chronic diseases in the elderly inpatients in recent 5 years was analyzed. Results From 2008 to 2012, the top 5 chronic diseases were hypertension (19.60%), coronary atherosclerotic heart disease (15.90%), malignant tumors (13.20%), diabetes mellitus (10.40%) and abnormal lipid metabolism (9.80%). From 2013 to 2017, the top 5 chronic diseases were hypertension (40.00%), malignant tumors (25.92%), diabetes mellitus (19.16%), coronary atherosclerotic heart disease (17.58%) and cataract (15.70%). During 2013 and 2017, there were different statuses of comorbidity among the elderly patients at different ages. The number of comorbidities was (2.71±1.86) in the 60-69-year-old patients,(4.24±1.54) in the 70-79-year-old patients, and(5.93±2.33) in the 80-89-year-old patients. Conclusion The prevalences of malignant tumors, hypertension and cataract are significantly increased in the elderly inpatients in our hospital. The number of chronic diseases is elevated with age. Geriatricians should diagnose and treat the diseases in the elderly in a comprehensive manner.