A positioning control device according to an embodiment includes an amplifier that includes a converter that rectifies and outputs an AC power supply to bus-bars; a smoothing capacitor that smoothes an output of the converter and generates a bus voltage; a regenerative resistance and a regenerative transistor; an inverter that supplies a drive current; and a command generation unit that generates a position command value for positioning control of a mechanical load in accordance with a command pattern. The inverter is connected between the bus-bars and supplies the drive current. The command generation unit acquires a regenerative-power-amount estimated value and an energy value storable in the smoothing capacitor; and on the basis of a result of a comparison between these values, it decides whether to use the position command value on the basis of the command pattern.