Disclosed is a caster control apparatus for a suspension of a vehicle. When the vehicle travels on a road which causes a vehicle body to lean to one side, the caster of a lowered wheel is increased, and the caster of a raised wheel is decreased, such that the casters of the wheels on both sides are offset with each other. Therefore, the vehicle is inhibited from leaning due to the lateral slope of the road, and the straight-line stability of the vehicle can be reliably maintained.