Lens barrel and lens assembly

A lens barrel that has a reference surface formed in a circular-arc shape and a first side surface formed in a cutout shape and fixes a lens such that an optical axis is lined along a central axis, the lens barrel comprising:

• a lens-receiving surface that extends in an intersection direction intersecting the central axis;
• a side frame portion that comes in contact with the lens-receiving surface in the intersection direction and that protrudes in a direction of the central axis from the lens-receiving surface;
• and
• a plurality of caulking portions that are formed at a tip portion of the side frame portion in a protruding direction and are deformed by external pressure to caulk and fix the lens between the caulking portions and the lens-receiving surface,
• wherein the lens-receiving surface is formed so as to be axisymmetrical to the central axis.