To efficiently use radio resources used in transmission of SRS, a base station apparatus (eNode B) transmits a scheduling grant including an instruction for transmission of a Sounding Reference Signal (SRS), and a mobile station apparatus (UE) transmits the SRS in response to the scheduling grant. The SRS is transmitted in the same subframe, another subframe or a previous subframe by the predetermined number of subframes as, immediately before, or before a subframe of a PUSCH (Physical Uplink Shared Channel) that the scheduling grant instructs to transmit.