A distal-end rigid section of an insertion section of an endoscope, includes: a first base of a metallic material with a columnar shape, the first base including a circular through-hole penetrating in an axial direction of the insertion section and a non-circular through-hole which is juxtaposed with the circular through-hole and is accessible to an outer peripheral surface of the first base and a second base of a resin material with an electrical insulation property, the second base being airtightly and watertightly formed as one piece with the first base on an axially proximal-end side of the first base, the second base airtightly and watertightly covering inner peripheral surfaces of the circular through-hole and the non-circular through-hole from the first base, a hole portion being formed on an inside of the covered inner peripheral surface of the non-circular through-hole such that at least one of an illumination light source and a light source board disposed on a proximal-end side of the illumination light source is disposed in the hole portion.