A mobile terminal in a mobile communication system supporting device to device (D2D) communication, and a method for operating the mobile terminal are provided. The terminal includes a first radio frequency (RF) chain configured to transmit a mobile communication signal and a second RF chain configured to receive a mobile communication signal, for mobile communication with a base station, a switching unit including a plurality of switches configured to establish transmission and reception paths in the first and second RF chains, and a controller configured to control switching of the switching unit to establish transmission and reception paths of a D2D communication signal for D2D communication by combining a part of the first RF chain with a part of the second RF chain. The combination of the parts of the first and second RF chains is different according to a D2D communication frequency band.