Three driving means for rocking a rocking object are provided, each of the foregoing driving means has a motor and an arm which rotates with one end thereof as an axis by the rotation of the motor, the other end of the foregoing arm is rotatably mounted to the front central portion and the rear both side portions of the foregoing rocking object, and each of the foregoing driving means is drivingly controlled to thereby pitch, roll and heave the foregoing rocking object. Such a rocking device capable of performing complicated operations with simple structure will be provided.