A control device controls non-excitation-actuated electromagnetic brake operation. The control device includes an electronic component having a characteristic that when an inter-terminal voltage of two electrodes is equal to or higher than a predetermined voltage, a resistance value is lower than when the voltage is lower than the voltage and a diode disposed such that a cathode is on a side having a higher potential than an anode. The coil in the non-excitation-actuated electromagnetic brake and the electronic component are connected in series to form a first series circuit, the first series circuit and the diode are connected in parallel, and the electronic component is connected in series with the coil provided in the non-excitation-actuated electromagnetic brake so as not to be conducted when the inter-terminal voltage is lower than the predetermined voltage, but to be conducted when the inter-terminal voltage becomes equal to or higher than the predetermined voltage.