The invention discloses an automobile speed measurement and control method and system. According to the method, the speeds and deflection angles of two front wheels are measured in real time, meanwhile, the gravity center of an automobile is determined according to values of gravity sensors at four axles as well as the wheel base and the tread of the automobile, the moving speeds, around an instantaneous center during turning of the automobile, of the left front wheel and the right front wheel of the automobile are converted into the moving speeds in the gravity center position of the automobile respectively, the average value of the two automobile speeds in the gravity center position of the automobile is taken as the actual travel speed during turning of the automobile, and the automobile speed can be controlled simultaneously according to the stress conditions of the four wheels. The problems that the control accuracy is reduced and a travel accident is likely to cause due to the fact that the automobile speed accuracy is not high during turning of the automobile because an automobile speed measurement device adopts the rotation speed of a transmission output shaft for automobile speed conversion in the prior art are solved, and high practical value is realized.