The present invention provides a cyclone separator comprising a cyclone portion for generating an eddy flow at a given flow rate by feeding a liquid containing a fine substance from liquid discharge passageways, for transferring the fine substance to an outer side by applying a centrifugal force to issue the fine substance-free liquid from a liquid flow-out passageway, and for precipitating the fine substance by decelerating the eddy flow. The liquid discharge passageways are disposed at plural sites; and the cyclone separator further comprises a liquid pressurizing chamber formed around the plural liquid discharge passageways in communication therewith; and a liquid introduction passageway for introducing the liquid containing the fine substance into the liquid pressurizing chamber.