A radio frame and method are provided for sending a sounding reference signal (SRS) in a mobile communication system, which is used to solve the problem of shortage of resources for sending the SRS in the mobile communication system. The method includes a user equipment (UE) sending the SRS to eNB in time-frequency resources corresponding to a guard space in the radio frame, wherein, the guard space is one or more of downlink to uplink guard space, uplink to downlink guard space, reserved subframes, or reserved idle resources. A device is also provided for sending the SRS, applied to the UE in the mobile communication system, wherein the device includes a radio frame construction module and a sounding reference signal transmission module.