A simple and compact lens protection mechanism for protecting an optical lens system in a lens barrel comprises a lens barrier member rotatable in a plane perpendicular to an optical axis between an open position for uncovering the optical lens system and a closed position for covering the optical lens system, a neutralizing spring incorporated with the lens barrier member, and a barrier drive ring operationally coupled to the lens barrier member by the neutralizing spring. The barrier drive ring is rotatable in opposite directions so as to drive the lens barrier member through the neutralizing spring between the open position and the closed position.