The cleaner includes a main body having an opening, a suction motor accommodated in the main body and configured to generate suction force, an opening cover separably coupled to the main body and configured to cover the opening, and a filter mechanism accommodated in the main body through the opening and configured to filter foreign substances of air discharged by the suction motor. When the opening cover is separated from the main body, at least a portion of the filter mechanism protrudes to the outside of the main body through the opening. While the opening cover is coupled to the main body, at least a portion of the filter mechanism protruding to the outside of the main body is pressed by the opening cover so as to be accommodated in the main body.