A lens barrel including a first moving lens group for advancing light of a subject onto an image plane, a second moving lens group for advancing light of the subject onto the image plane, a shaft section for guiding the first moving lens group and the second moving lens group in a direction of an optical axis, an intermediate positioning section for supporting the shaft section at an intermediate portion of the shaft section, and an end positioning section for supporting one end of the shaft section, wherein the first moving lens group slides on a portion of the shaft section that is closer to the subject than the intermediate positioning section is, and wherein the second moving lens group slides on a portion of the shaft section that is closer to the image plane than the intermediate positioning section is.