Cyclonic dust collection unit and filter structure thereof

Provided is a cyclonic dust collection unit for conveniently removing a foreign object filtered therein. The cyclonic dust collection unit includes: a first filtering chamber for filtering a first foreign object having a first size using a cyclone airflow; a second filtering chamber for filtering a second foreign object having a second size smaller than the first size of the first foreign object, the second foreign object being contained in the air passed through the first filtering chamber; a foreign object storing chamber for storing the first and/or second foreign object(s) separated through the first and second filtering chambers; a filter disposed in the first filtering chamber, for separating the first foreign object on an outer surface thereof; and a cutaway hole formed in a longitudinal direction thereof.