A radio communication apparatus add an information element (ACK/NACK information element) indicating a reception result of a received signal of a transmission sequence number to the another information element (Other ACK/NACK information element) indicating a reception result of a received signal of another transmission sequence number, which information elements are transmitted to the another radio communication apparatus; and the another radio communication apparatus judges a reception result of the transmitted signal on the basis of the information element and the another information element received from the radio communication apparatus.