This paper presents a disturbance-force compensator for an electrodynamic shaker. The characteristics of a shaking system are considered to be nonlinear and variable because of the influence of the test piece. In order to compensate for this problem, the influence of the disturbance force needs to be suppressed. The controller is designed using μ -synthesis by considering the uncertainty of the shaker. In order to investigate the control performance in relation to the influence of friction and sloshing, time waveform replication testing is executed. Finally, because the compensator suppresses nonlinearity, a good performance can be realized, as confirmed by experiments conducted using actual equipment.