A compact and power saving imaging-element unit of handshake compensation type is provided. The imaging-element unit comprises an imaging-element board with an imaging element that performs photoelectric conversion of incident light formed or located thereon; a relay board that is disposed between the imaging element and an external control board, and that receives signals between the imaging-element board and the external control board; and a package with at least the imaging-element board and the relay board contained therein; wherein a slider mechanism is disposed between the imaging-element board and the relay board for moving the imaging-element board to compensate handshake of an imaging device.