Provided is a suspension control system that allows a state variable of a vehicle used for the damper damping force control to be computed at a high precision without regards to the caster angle given to the suspension geometry. A suspension control system (20) for a vehicle (V) provided with a variable damper (6) that can adjust a damping force according to an input signal (V W ) comprises a wheel rotational speed sensor (9) for detecting a wheel rotational speed (V W ), a gain circuit (37) for computing the unsprung load (u 1 ) of each wheel (3) according to the wheel rotational speed variation (”V W ) detected by the wheel speed sensor (9), a single wheel model computing unit for computing the sprung velocity (S 2 ) and the stroke speed (Ss) by inputting the unsprung load (u 1 ) to a single wheel model (38) representing the behavior of the vehicle, and a damper control unit (25) for controlling a damping force of the variable damper (6) according to the computed sprung velocity (S 2 ) and stroke speed (Ss).