This paper presents an experimental study of a tracking control of a shape memory alloy (SMA) wire actuator using a nonlinear robust compensator. The control design uses the sliding-mode approach and requires no detailed information about the SMA model. To test the effectiveness of the proposed controller, experiments of the tracking control of an SMA wire actuator are conducted. Experimental results show that the SMA wire actuator under the robust control can precisely follow a sinusoidal path, and the effectiveness of the proposed control strategy is thus demonstrated.