A multicarrier communication base station device (1) in accordance with the present invention includes selection unit that selects a subcarrier to be allocated based on transmission rate information in each mobile station (2), evaluation value calculation unit that calculates a reference value of a transmission rate with regard to a subcarrier to be allocated based on transmission rate information in each mobile station (2) and then calculate an evaluation value that is obtained by evaluating a difference between the reference value and a transmission rate of a subcarrier excluded from allocation, and priority determination unit that determines a priority of a mobile station to be assigned to each subcarrier based on an evaluation value calculated by the evaluation value calculation unit.