In a vacuum cleaner, by including a casing having a certain internal space; a suction force generating unit installed in the casing to generate a suction force and discharge sucked air; a head unit combined with the casing to suck impurities on the bottom with air by a suction force of the suction force generating unit or discharge air sucked from the outside; a filter unit for filtering off impurities in air sucked through the head unit or ambient air received from the outside; a flow channel switch connected with the head unit, the filter unit and the suction force generating unit so as to selectively switch a flow channel in order to guide air including impurities sucked through the head unit by the suction force of the suction force generating unit or make ambient air introduced in the flow channel switch flow to the head unit; and plural pipes for providing passages of air flowing in the head unit, the filter unit, the suction force generating unit and the flow channel switch, it is possible to perform not only a function for suctioning those on the surface to be cleaned but also a function for blowing dirt or debris lay on curtains or window frames.