OBJECTIVE: The aim of this study was to analyze the epidemiological characteristics of mortality in the emergency department of Beijing Tongren Hospital from 2014 to 2019. METHODS: A total of 781 cases in the hospital’s emergency department that resulted in mortality were retrospectively screened, and epidemiological and analytical methods were used to analyze the epidemiological characteristics and the trend of adult mortality in the emergency department of our hospital. RESULTS: Of the 781 selected cases, 448 were male, and 333 were female. Mortality rates were highest in patients aged 80–89 years, and most of the patients were retired (71.57%). Infection disease was associated with the highest mortality rate (44%), followed by cardiovascular disease and malignant tumors. CONCLUSION: Infectious diseases, cardiovascular diseases, and malignant tumors are the major threats to the lives of patients in the hospital’s emergency department. The cause of death differs depending on the patient’s age.