PURPOSE: To prevent the rolling of a car in a curved place and improve its driving stability in a vehicle shock absorber, by constituting the shock absorber such that a difference of speed between front left and right wheels is detected to adjust damping force of the shock absorber in accordance with said difference of speed.

CONSTITUTION: Detected car speeds of car speed sensors 2, 3 of front left and right wheels are input to a microcomputer 1 through buffers 4, 5 to calculate the absolute value of a speed difference between the wheels and compare the value with a reference value. If it is at least the reference value, a damping force increase signal is output after a prescribed time to absorber driving circuits 10W13 and increase damping force of corresponding absorbers 6W9. While, if it is less than the reference value and the damping force of the absorbers 6W9 is decided to be high, a decrease signal of damping force is output after a prescribed time to the circuits 10W13 to decrease the damping force of the absorbers 6W9. By this constitution, the rolling of a car at its cornering operation can be prevented to improve driving stability.