To provide a solenoid drive device improved in power efficiency for drive controlling an actuator using a solenoid and an active vibration-control supporting device improved in power efficiency which includes the solenoid drive device.

The solenoid drive device includes a booster circuit 120 for boosting a battery voltage, and driver circuits 121A and 121B control-driven by power boosted and supplied by the booster circuit 120. An ACM_ECU 200A incorporating a microcomputer 200b makes a vibrating state estimating section 234 and a phase detecting section 235 calculate the magnitude of engine vibration, a cycle of engine vibration and a phase lag for acquiring a drive frequency fDV of the actuator. A booster circuit control section 237 of the microcomputer 200b determines a target voltage value V* based on the drive frequency fDV. The target voltage value V* is inputted to the booster circuit 120, and desired power is fed to the driver circuits 121A and 121B from the booster circuit 120 at the target voltage value V*.