Abstarct: An active suspension system establishes a tradeoff between the comfort and handling which are the two desired goals and however are opposite to each other. The proposed control system includes two loops namely a position control loop and a force control loop. A model reference adaptive control is used in the position control loop for tracking purpose. This controller is robust against varying parameters such as the sprung mass and the stiffness of tire. The reference model which is defined by an impedance rule, relates the displacement of body to the produced force due to road disturbances. The required feedbacks are only the body displacement and body acceleration. The sliding mode method is used in the force control of hydraulic actuator which results in a robust system subject to parametric uncertainties. Comparing this method with proportional control shows that the proposed approach is more robust against parametric uncertainties and produces a less tracking error. The stability of control system is analyzed and simulation results confirm that the adaptive impedance control of an active suspension system is robust subject to parametric uncertainties with a good performance.