Background: Trauma is the third cause of death in the world, just below to cardio-vascular diseases and cancer. It caused more than 600 000deaths in China in 2012. Trauma has brought serious burden to the families and the society. Among all types of injury, traffic injury is one of the biggest causes of serious injury which always leads to disability or even death. Objectives: The aim of this study was to analyze the epidemiological characteristics of traumatic in-patientsand to compare traffic injury with other types of injury. Patients and methods: This cross-sectional study was a retrospective, descriptive and analytical study on traumatic in-patients from January 2009 to January 2015 in Peking University of peoples hospital. Demographic data, type of injury, injury severity score (ISS), length of hospitalization, diagnoses and department of in-patients were recorded. Results: 5085 patients, aged from 0 to 100 years, were obtained in this study, including 2723 male (53.5%) and 2362 female (46.5%). Its average age was 52.1 years old. The most prevalent type of injury was fall (71.2%), followed by traffic injury (7.4%) and penetrating injury (5.6%).There were 374 patientsin traffic injury group with an average age of 48.6 (male 59.6%, female 40.4%). The average ISS of traffic injury group was 8.78, which was significant higher than that of the other group (5.77) (p<0.01). The average length of hospitalization was 15.23 days. It was also significant bigger than that of the other group (10.37days)(P<0.01). Conclusions: Like some developed countries, the commonest type of injury was fall, followed by traffic injury. Traffic accidents lead to more serious injury than other types of injury, which cause more days of hospitalization.