The dust collector, that may be used in vacuum cleaner, includes: a primary cyclone unit separating dust from air introduced from outside the dust collector; and a secondary cyclone unit defining axial cyclone bodies separating fine dust from air introduced in an axial direction. The secondary cyclone unit includes casings having outer walls around hollow portions; and a fine dust separating member disposed on the casings to form the axial cyclones. The fine dust separating member includes vortex finders disposed in the casings; band portions enclosing an outer circumferential surface of the vortex finders at a position spaced from the vortex finders, and having a shape corresponding to the casings so as to form the axial cyclones together with the casings; and guide vanes disposed between the vortex finders and the band portions and extending in a spiral direction to induce a rotational flow of air.