A lens barrel includes a lens mount, a fixed frame, and a movable frame. The lens mount includes an attachment part to which the fixed frame is attached, and a recessed part which is adjacent to the attachment part and is recessed toward the camera body, and into which an end part of the movable frame enters at least when the movable frame is positioned closest to the lens mount. Part of the attachment part close to the camera body has a tapered surface inclined relative to the optical axis. A counterbore in which a screw for attaching the fixed frame to the attachment part is disposed is formed at the tapered surface. Due to the tapered surface, part of the lens mount where the attachment part is formed has a thickness greater than that of another part of the lens mount where the recessed part is formed.