A vibration damping device which is able to damp vibration of a rotating body in a high-speed range and to certainly accelerate the rotating body to the high-speed range is provided.
A vibration damping device 1 damping vibration of a rotating body 100 includes an automatic balancer 2 which is configured to cancel out imbalance of the rotating body 100 when the rotating body rotates 100; a liquid damper 4 which is coaxially rotatable with the rotating body 100 and includes a collision member 23 provided in a casing 20 in which liquid 22 is sealed, the liquid colliding with the collision member 23 when the liquid 22 moves in a circumferential direction; and a relative rotation unit 5 which is configured to cause the liquid damper 4 to rotate relative to the rotating body 100.