In a radio communication system that simultaneously uses plural radio channels, a radio communication apparatus can quickly secure plural radio channels simultaneously used for radio communication while preventing collision with a radio signal transmitted by another radio communication apparatus so away from the radio communication apparatus that the radio communication apparatus cannot detect radio waves.A radio communication apparatus STA1 according to the present invention includes a receiving unit 10 which receives, when a first signal is transmitted via each of the plural radio channels, the first signal though at least one or more radio channels among the plural radio channels, and performs carrier sense for each of the plural radio channels used for the transmission of the first signal, a selecting unit 40 which selects a radio channel used for radio communication out of radio channels set in a standby state, and a transmitting unit 20 which transmits a response signal for the first signal via the selected radio channel.