Abstract: A vibration damping apparatus utilizing the phenomenon of an apparent viscosity created by the combination of a magnetic body and a magnetic fluid due to the magnetic fields of the magnetic fluid. The apparatus is a piston system, including an inner cylinder formed of a magnetic body accommodated within an outer cylinder formed of a nonferrous material. A passage of suitable dimensions is defined between the outer peripheral surface of the inner cylinder and the inner peripheral surface of the outer cylinder. A magnetic fluid is stored within the outer cylinder. The inner cylinder is firmly secured at its upper face to a supporting shaft formed of a nonferrous material. The supporting shaft is provided at its upper end with an upper frame for suitable devices through a planar plate when the apparatus is used as a vibration proofing frame. Likewise, lower frame is arrange under the lower face of the outer cylinder portion.