A cyclone dust-collecting apparatus to separate dust from air drawn in through a suction port body of a vacuum cleaner using a centrifugal force and to collect the separated dust is provided. The cyclone dust-collecting apparatus includes a primary cyclone unit to separate dust from air drawn in through the suction port body; a secondary cyclone unit disposed inside the primary cyclone unit to separate dust from air discharged from the primary cyclone unit; and a tertiary cyclone unit disposed above the primary cyclone unit at an angle different from the primary and secondary cyclone units.