A lens barrel includes a housing having a ring portion surrounding an optical
axis;
a first optical element and a second optical element which are positioned radially
inside the ring portion and which are movable along the optical axis relative to
the housing; a support frame which supports the second optical element, and has
at least one radial arm portion which projects radially outwards to such an extent
that an outer end of the radial arm portion is positioned radially outside the
ring portion of the housing; and at least one guide shaft positioned radially outside
the ring portion, and configured to guide the radial arm portion in the optical
axis direction.