A fluorine gas generating apparatus includes an electrolytic cell where the molten salt is retained and which is separated and divided above the liquid level of the molten salt into a first gas chamber where a product gas mainly containing a fluorine gas generated at an anode immersed in the molten salt is led and a second gas chamber where a byproduct gas mainly containing a hydrogen gas generated at a cathode immersed in the molten salt is led, and a refining device refining the fluorine gas by coagulating with a cooling medium and trapping a hydrogen fluoride gas evaporated from the molten salt in the electrolytic cell and mixed in the product gas generated from the anode. The cooling medium for coagulation of the hydrogen fluoride gas in the refining device and discharged is re-used as a utility gas used at spots in the fluorine gas generating apparatus.