A barrel assembly includes a barrel, at least one lens group disposed in the barrel to move in an optical axis direction, an aperture disposed in the barrel that adjusts an amount of light passing through the at least one lens group; and a light adjustment unit disposed in the barrel to move in the optical axis direction and that blocks light passing through a peripheral area of the at least one lens group when the at least one lens group is in at least one part of a travel section along which the at least one lens group moves in the barrel.