Traffic safety is one of the main priority all over the world. It is used to identify the causes and factors of road accidents where different approaches have been considered and has main aim to reduce the traffic accidents. This paper summarizes the work of applying data mining technologies to link recorded road characteristics to accident severity. The relationship between fatal rate and other attributes including collision manner, weather, surface condition, light condition, and drunk driver were investigated. It also predicts future behaviors and it also takes effective decisions to reduce accidents.