A capsule-type endoscope includes an illumination board (30) which is prepared to mount an illuminating electronic component (31) necessary to illuminate a test region of a test subject with illumination light an image sensor (13) which has a light-receiving surface including an effective area (B) and an ineffective area (C), the illumination light reflected from the test region being received to generate an image of the test region in the effective area, the ineffective area not contributing to the image generation an imaging board (10) which is arranged in parallel with the illumination board (30), the image sensor (13) being mounted on the imaging board and a component arrangement unit in which the illuminating electronic component (31) is arranged, the illuminating electronic component being provided in an area on the illumination board, the area on the illumination board being obtained by projecting the ineffective area (C) in the light-receiving surface of the image sensor (13) to a direction orthogonal to the light-receiving surface of the image sensor (13).
