To use CSI feedback information capable of sufficiently supporting MU-MIMO transmission and CoMP transmission in LTE-A systems, in a radio communication method of the invention, a radio base station apparatus (200) generates downlink transmission data including a report mode corresponding to a bandwidth to perform feedback of feedback information including channel quality information and spatial channel information, and an extension level of the feedback information, and multiplexes the downlink transmission data and a reference signal for feedback information to transmit to a mobile terminal apparatus (100), and the mobile terminal apparatus (100) receives a downlink signal including the report mode and the extension level, and generates feedback information associated with the report mode and the extension level to transmit to the radio base station apparatus (200).