Objective: To study the epidemiological characteristics and preventive methods of road traffic crashes in a mountain city in western China through sampling investigation of traffic crashes in different regions of Chongqing city in recent years. Methods: Two police teams of traffic management in downtown, two teams in suburb, one team in county and one freeway team were randomly selected, and road traffic crashes between 1988 and 1997 were investigated and analyzed. Results: A total of 13121 road traffic crashes with 6201 crashes with casualties were analyzed. The incidence of crashes was higher in May, June and July, and on Friday and Wednesday and at 8:00-12:00 and 14:00-18:00 within a day. Casualties were 44.0% in pedestrians and 42.5% in passengers of total casualties. The deaths and severe injuries in pedestrians were59.1% of total deaths and 56.4% of total severe injuries. The age of drivers and passengers were mainly at 18-30 years, followed by 31-40 years. People over 60 years old accounted for 24.1% of total pedestrian casualty. Head injury was the most common reason for deaths. The main reasons for these crashes were improper driving and violating traffic laws. Violating traffic laws by pedestrian was one of the main reasons for pedestrian casualty. Conclusions: The crashes are related to the characteristics of geography, climate, society activity of people, and the sense of traffic safety, the basic traffic construction and management in Chongqing. The traffic casualty of pedestrian is a big problem in Chongqing. To prevent and decrease road traffic injuries effective methods should be worked out and propaganda on traffic safety and traffic management should be strengthened according to different characteristics of different regions. To strengthen the first aid and treatment of cranium-brain injury and chest-back injury is also helpful in decreasing traffic deaths.