A dust collector includes a first dust storing unit to collect dust firstly-separated from air by a first cyclone, a second dust storing unit to collect fine dust secondly-separated from the air by second cyclones located above the first cyclone, a lower cover part coupled to a first dust container to form a bottom surface of the first dust storing unit and the second dust storing unit, and rotatable about a hinge to simultaneously open the first and second dust storing units, such that the dust and the fine dust are simultaneously discharged, and a compression device rotatably connected to the lower cover part so as to rotate in a reciprocating manner to compress the dust collected in the first dust storing unit.