1. Human factors cause traffic accidents. For the traffic accidents in the highway, the most important factor is the human factor. For the expressway, it belongs to the closed highway, for the road surface and the surrounding driving environment, are higher than the general highway. Therefore, in the process of driving, it is easy to get a better driving experience. Therefore, when driving on the expressway, the driver's own safety consciousness drops, or his cognition level of common sense of high-speed traffic is not enough, as well as other relevant influencing factors, leading to the occurrence of high-speed traffic accidents. In the event of special weather problems, if there is rain, fog and icy road conditions, to strictly control their own speed, do not have the corresponding lucky mentality, otherwise it is easy to occur traffic accidents.