Provided is an apparatus for controlling subcarrier spacing in a system supporting multiple frequency bands. The apparatus for controlling a subcarrier spacing comprises: an interference detection unit detecting interference over multiple frequency bands; a system parameter provision unit providing system parameters related to a subcarrier spacing between the multiple frequency bands—for example RF, FFT size, and channel bandwidth; a subcarrier spacing control unit controlling the subcarrier spacing such that the detected interference is reduced, on the basis of the system parameters. In a system operating with multiple bands, different subcarrier spacing can be applied by each band, thereby controlling interference occurring in each band.