This article mainly studies the automotive collision avoidance system based on fuzzy control.This system selects and uses millimeter-wave radar to measure the distance between two cars and the speed of a motor vehicle.First of all,create the safety distance model of the motor vehicle brake.Secondly,design the fuzzy controller for early warning.Lastly,according to the national highway safety regulation,also by analyzing the related resources theoretically,it can be testified that this system can do the trick of collision warning.