An image blur compensation unit and image blur compensation device that can be made smaller in size. Wedge prisms, which refract light that is guided to an imaging element after passing through a lens group, are disposed on the same plane perpendicular to a central axis, and are supported by rotatable prism support portions. In order for the wedge prisms to be spaced by a predetermined distance and face each other along the central axis in a space that is formed when being placed adjacent to each other, the prism support portion supports the wedge prism on one end side along the central axis, and the prism support portion supports the wedge prism on one end side along the central axis. In this manner, the prism support portions supporting the wedge prisms, which need to be disposed along the central axis so as to be spaced by a predetermined distance and face each other, are disposed on the same plane. Therefore, the central axis-direction thickness can be made thinner, and the device can be made smaller in size.