A first radio base station (1A) measures the power of an interference, which is caused by a radio signal transmitted over a second uplink from a radio terminal (2B) to a second radio base station (1B), for one resource block or each of a plurality of resource blocks allocated to a radio terminal (2A), and further calculates a traffic amount ratio in the first radio base station (1A). Moreover, the first radio base station (1A) multiplies the interference power value for each resource block by the traffic amount ratio measured by a communication load measuring unit (152), then generates interference information for each resource block, which corresponds to the multiplication result value for each resource block, and then transmits the interference information to the second radio base station (1B).