The present invention relates a resource allocation method and a resource allocation device. According to an exemplary embodiment of the present invention, a resource allocation method of a wireless communication system includes: allocating a resource to a first base station; determining whether or not a second cell that is smaller than a first cell is provided in a first cell region managed by the first base station; reducing the resource allocated to the first base station when the second cell is provided; and allocating resources remaining after reducing the resource to a second base station that manages the second cell.