A vacuum cleaner, comprising: a suction body to draw in a dust or dirt along with an air from a surface to be cleaned; a cleaner body having a suction motor therein, the suction body being connected to a side of the cleaner body; and a cyclone dust collecting apparatus detachably coupled in the cleaner body, wherein the cyclone dust collecting apparatus comprises: a cyclone unit to form a first current turning in a first direction to separate the dust or dirt and the air drawn therein from each other and having a dust outlet to discharge the dust or dirt separated from the air; and a dust collecting unit to collect the dust or dirt discharged from the dust outlet, characterized in that the cyclone unit is disposed inside the dust collecting unit, the dust outlet has a side formed adjacent to an inner wall (116, 117) of the dust collecting unit to form a second current turning in a second direction opposite to the first direction thus to allow the dust or dirt discharged through the dust outlet to whirl along the inner wall (116, 117) of the dust collecting unit in the dust collecting unit, wherein the dust outlet comprises an extension rib to guide the dust or dirt toward the inner wall (116, 117) of the dust collecting unit. a suction body to draw in a dust or dirt along with an air from a surface to be cleaned; a cleaner body having a suction motor therein, the suction body being connected to a side of the cleaner body; and a cyclone dust collecting apparatus detachably coupled in the cleaner body, wherein the cyclone dust collecting apparatus comprises: a cyclone unit to form a first current turning in a first direction to separate the dust or dirt and the air drawn therein from each other and having a dust outlet to discharge the dust or dirt separated from the air; and a dust collecting unit to collect the dust or dirt discharged from the dust outlet, characterized in that the cyclone unit is disposed inside the dust collecting unit, the dust outlet has a side formed adjacent to an inner wall (116, 117) of the dust collecting unit to form a second current turning in a second direction opposite to the first direction thus to allow the dust or dirt discharged through the dust outlet to whirl along the inner wall (116, 117) of the dust collecting unit in the dust collecting unit, wherein the dust outlet comprises an extension rib to guide the dust or dirt toward the inner wall (116, 117) of the dust collecting unit. a cyclone unit to form a first current turning in a first direction to separate the dust or dirt and the air drawn therein from each other and having a dust outlet to discharge the dust or dirt separated from the air; and a dust collecting unit to collect the dust or dirt discharged from the dust outlet, characterized in that the cyclone unit is disposed inside the dust collecting unit, the dust outlet has a side formed adjacent to an inner wall (116, 117) of the dust collecting unit to form a second current turning in a second direction opposite to the first direction thus to allow the dust or dirt discharged through the dust outlet to whirl along the inner wall (116, 117) of the dust collecting unit in the dust collecting unit, wherein the dust outlet comprises an extension rib to guide the dust or dirt toward the inner wall (116, 117) of the dust collecting unit.