Multi-cyclone dust collector for vacuum cleaner

The present invention relates to a multi-cyclone dust collector for a vacuum cleaner. The multi-cyclone dust collector includes a first cyclone (10) forcing contaminants-laden air that is drawn-in at a lower portion of the first cyclone (10) to form an upwardly whirling air current so as to centrifugally separate contaminants therefrom air, a first contaminants chamber (30) wrapping around a first part of the first cyclone (10) and collecting contaminants discharged from the first cyclone (10), and a second cyclone unit (50) wrapping around a second part of the first cyclone (10) and having a plurality of second cyclones (50), each of the plurality of second cyclones (50) drawing-in semi-clean air discharged from the first cyclone (10) at an upper portion of each of the plurality of second cyclones (50) so as to centrifugally separate fine contaminants from the semi-clean air.