Traffic safety is closely related to everyone’s daily life, it is also a major public health threat. Information based on assessment of road safety issues is necessary for everybody since they provide a reference and basis for policy improvement such as speed limit, driving lessons and so on. This study analyzed the main cause of fatal road traffic crashes from the aspects of time when accidents occurring, gender, age of driver and the speed limit at that time and use symbolic regression to analyze the main cause of fatal accident. The result shows that the time of accident, ages of drivers are closely related to the occurrence of fatal accident. The impact of the speed of the car is slightly weaker in the event of an accident;driver’s gender has the minimal impact.