To provide an apparatus for decomposing fluorine series compound gas with which fluorine series compound gas can be decomposed efficiently by enhancing the performance to concentrate the fluorine series compound gas contained in exhaust gas.

This apparatus for decomposing the fluorine series compound gas is provided with a gas concentrating unit 2 for concentrating the fluorine series compound gas by supplying to the unit 2 the gas to be treated which contains at least one fluorine series compound gas and consists of a plurality of gases and selectively permeating/separating only the gases other than the fluorine series compound gas by a gas separating filter 4 in the unit 2 and a gas decomposing unit 3 for decomposing the fluorine series compound gas concentrated by the unit 2. The unit 3 is operated in a heated state and the heat generated in the unit 3 is used for warming the filter 4.