Provided are a base station apparatus and an information transmitting method capable of enhancing frequency diversity effect and improving reception quality characteristics at a mobile terminal apparatus even when a system bandwidth is extended. The information transmitting method comprises: using reception quality information from the mobile terminal apparatus as a basis to select one or more than one group band from a set of group bands obtained by dividing a system band (ST302), selecting schedule information by comparing data rates of an overall system obtained after allocating transmission data to the group bands (ST309, ST310); and transmitting the transmission data scheduled in accordance with the schedule information to the mobile terminal apparatus on downlink.