An endoscope includes: a cylindrical member a ring member, in which the cylindrical member is fixed a recess portion provided in an outer circumferential face of the cylindrical member a first recess wall formed in a direction around an axis in the recess portion a second recess wall formed along a direction of the axis a projection portion provided on an inner circumferential face of the ring member, the projection portion being engaged with a recess portion a first contact portion that comes into contact with the first recess wall in the direction of the axis and a second contact portion that comes into contact with the second recess wall in the direction around the axis.
