A capsule endoscope comprising: an illumination board section (20R1) in which an illumination unit for emitting illumination light illuminating a tested region of a subject is arranged; an imaging board section (20R2) in which an image sensor imaging the tested region of the subject is arranged; a flexible wiring board section which is connected to the illumination board section (20R1) and the imaging board section (20R2), the flexible wiring board section being made from a flexible material in which the illumination board section (20R1) and the imaging board section (20R2) are integrally formed; a lens support member which supports a lens for focusing reflected light of the illumination light from the tested region and has a cylindrical member whose one end side is positioned with respect to the image sensor; a hole which is made while piercing through the illumination board section (20R1), has an inner diameter larger than an outer diameter of the lens support member in order to fit the lens support member in the hole; and a front cover comprising an abutting surface, which is located on the proximal end side of the front cover and extends in the direction orthogonal to the axial center of the front cover, the abutting surface engagedly abutting a mounting surface of the illumination board section (20R1) wherein the lens support member includes a large diameter portion which is positioned with respect to the image sensor, is formed on the one end side, and has an outer diameter of a predetermined size; a small diameter portion which is inserted into and fitted in the hole, is formed on the other end side, and has an outer diameter smaller than the one end side; and a step portion which is formed at a boundary between the large diameter portion and the small diameter portion, wherein the abutting surface positions and supports the illumination board section (20R1) with respect to the lens support member by causing the illumination board section (20R1) to abut on the lens support member when the other end side of the lens support member is inserted into and fitted to the hole, a reinforcement portion extends from a lower edge portion of the lens support member, the lens support member includes a base which is integrally formed with a proximal end portion of the cylindrical member, and abutting portions that extend downward from two adjacent sides of the lower edge portion, and the reinforcement portion has substantially the same shape as the abutting portions, and is provided separately from the abutting portions. an illumination board section (20R1) in which an illumination unit for emitting illumination light illuminating a tested region of a subject is arranged; an imaging board section (20R2) in which an image sensor imaging the tested region of the subject is arranged; a flexible wiring board section which is connected to the illumination board section (20R1) and the imaging board section (20R2), the flexible wiring board section being made from a flexible material in which the illumination board section (20R1) and the imaging board section (20R2) are integrally formed; a lens support member which supports a lens for focusing reflected light of the illumination light from the tested region and has a cylindrical member whose one end side is positioned with respect to the image sensor; a hole which is made while piercing through the illumination board section (20R1), has an inner diameter larger than an outer diameter of the lens support member in order to fit the lens support member in the hole; and a front cover comprising an abutting surface, which is located on the proximal end side of the front cover and extends in the direction orthogonal to the axial center of the front cover, the abutting surface engagedly abutting a mounting surface of the illumination board section (20R1) wherein the lens support member includes a large diameter portion which is positioned with respect to the image sensor, is formed on the one end side, and has an outer diameter of a predetermined size; a small diameter portion which is inserted into and fitted in the hole, is formed on the other end side, and has an outer diameter smaller than the one end side; and a step portion which is formed at a boundary between the large diameter portion and the small diameter portion, wherein the abutting surface positions and supports the illumination board section (20R1) with respect to the lens support member by causing the illumination board section (20R1) to abut on the lens support member when the other end side of the lens support member is inserted into and fitted to the hole, a reinforcement portion extends from a lower edge portion of the lens support member, the lens support member includes a base which is integrally formed with a proximal end portion of the cylindrical member, and abutting portions that extend downward from two adjacent sides of the lower edge portion, and the reinforcement portion has substantially the same shape as the abutting portions, and is provided separately from the abutting portions.