a first collecting unit having an air suction port, the first collecting unit separating large-sized contaminants from an air that is drawn through the air suction port;

a cyclone body comprising a second cyclone in fluid communication with the first collecting unit and a plurality of third cyclones arranged around and in fluid communication with the second cyclone, the second cyclone separating middle-sized contaminants from the drawn air and the plurality of third cyclones separating small-sized contaminants from the drawn air;

an air discharge port in fluid communication with the cyclone body, through which the air is discharged after passing through the plurality of third cyclones; and

a contaminant receptacle provided at a lower end of the cyclone body, the contaminant receptacle collecting the middle-sized and small-sized contaminants, wherein the first collecting unit comprises:

a housing having the air suction port at a lower part;

a first discharge port spaced a predetermined distance upward from the air suction port, the first discharge port being provided in an inner wall of the housing facing the air suction port; and

a guide provided to an inner side of the housing, and guides the drawn air from the air suction port to discharge through the first discharge port after the drawn air collides against the inner wall of the housing.