Where two axes X and Y using the axial center position as the origin are set on a section orthogonal to the axial line of the distal end hard portion, the observation portion and the treatment equipment lead-out portion are disposed at both side positions between which the Y-axis is placed, the surface on which the solid-state image pickup device of the substrate is incorporated is disposed in a direction parallel to the X-axis, the center of the treatment equipment lead-out port is disposed between a plane parallel to the X-axis including the center of the optical axis of the object lens and a plane including the plane of the substrate, the line connecting the centers of both the illumination portions are roughly parallel to the Y-axis, and is drawn near the center of the optical axis of the object lens, and the distances between the center of the optical axis and both the illumination portions are made as equal to each other as possible.