To define the situation of traffic safety about highway passenger transport accurately, and reveal the statistical regularity of braking safe performances on long distance buses, based on large sample braking performance detection of a given type long distance buses, the statistical models about 4 braking performance were established. This research shows that the unqualified rate of front axle braking force balance performance of the given type long distance buses beyond 24%, and the rear one is 7% as well, which could be one serious hidden danger. The models established have very high calculating precision. What makes this conclusion more persuasive is the relative error maximum between model calculating values and real detecting results is 0.428% only. In addition, the practicable direction and way to solve the exposed problem in vehicle braking system are given. The research results can be used to understand the braking performance statistical regularity of typical long distance bus accurately, providing a reliable technical guarantee for improving traffic safety.