A radio base station transmits downlink control information to user terminals through enhanced PDCCHs which are frequency-division-multiplexed with a PDSCH, and includes an allocation section that allocates a plurality of enhanced PDCCH sets to each user terminal, the plurality of enhanced PDCCH sets each including a plurality of PRB pairs placed for the enhanced PDCCHs, so that at least one enhanced PDCCH set overlaps with other user terminals, and a mapping section that selects enhanced PDCCH sets from the plurality of enhanced PDCCH sets so that the number of enhanced PDCCH sets used to transmit the downlink control information in a predetermined time resource unit becomes minimum, and maps the downlink control information to the PRB pairs which form the selected enhanced PDCCH sets.