Objective To explore the disease composition of the death cases in a hospital in the last 4 years,  and to provide reference for disease prevention and treatment. Methods All detailed information of inpatients′ deaths from January 2016 to December 2019 was extracted to classify the diseases according to international Classification of diseases (ICD-10), and the age, sex, and disease composition of the death cases was analyzed. Results A total of 2 266 patients died in the hospital from 2016 to 2019, with a fatality rate of 0.8%. The number of hospitalized patients increased year by year, while the fatality rate decreased year by year (P<0.05). There were 1,431 male deaths and 835 female deaths, with a male-to-female ratio of 1.71 to 1. Diseases of the tumor system (30.6%), circulatory system (27.5%) and respiratory system (17.9%), cause of injury poisoning (10.6%) and digestive system (6.1%) ranked the top 5, accounting for 91.7% of the total number of deaths. The first two causes of death in males and females were the same, both were other respiratory diseases and pulmonary malignancies, and there was no gender difference between the two diseases (P>0.05). In addition to tumor and injury poisoning, circulatory, respiratory and digestive diseases were on the rise with age. Except for respiratory diseases, other four diseases showed a downward trend over 70 years old. Conclusion The prevention and treatment of tumors, circulatory diseases and respiratory diseases should be targeted to reduce the fatality rate. According to the characteristics of diseases at all ages, targeted preventive measures can reduce the risk of death and improve the quality of life.