A cyclone dust collecting apparatus comprises at least one second cyclone unit having a first cyclone unit, an air passage for guiding air discharging via the first cyclone unit, and a discharge pipe wherein the discharge pipe comprises a passage guide member for guiding air discharged from the second cyclone unit. Because the passage guide member is mounted in the discharge pipe of the second cyclone part, a load of suction source reduces to decrease power consumption for operation of a cyclone dust collecting apparatus.