This paper presents a sliding mode controller for a “soft” 2-DOF planar pneumatic manipulator actuated by pleated pneumatic artificial muscle actuators. Since the actuator dynamics is not negligible, an approximate model for the pressure dynamics is taken into account. This makes it necessary to perform full input-output feedback linearization in order to design a sliding mode controller. The design of the controller is presented in detail and experimental results obtained by implementing the controller are discussed.