A radio communication system (1) includes a pico-cell base station (PeNB) which is located in the communication area of a macro-cell base station (MeNB) and the transmission power of which is lower than that of the macro-cell base station (MeNB). For radio resources that can be used as PDSCH, a resource division ratio that is a ratio between unusable PDSCH resources, which cannot be used by the macro-cell base station (MeNB), and usable PDSCH resources, which can be used by the macro-cell base station (MeNB), is decided, and a radio resource is allocated, out of the usable PDSCH resources defined in accordance with the decided resource division ratio, to a radio terminal that is to connect to the macro-cell base station (MeNB). The resource division ratio is decided based on the traffic load of each base station.