Provided are a co-time co-frequency full duplexing system and a mobile terminal. The co-time co-frequency full duplexing system includes a baseband processing circuit, a transmitting terminal signal processing circuit, a receiving terminal signal transmission circuit, a signal transceiver circuit. A first end of the baseband processing circuit is electrically connected to a first end of the transmitting terminal signal processing circuit, a second end of the transmitting terminal signal processing circuit is electrically connected to a first end of the signal transceiver circuit, a second end of the baseband processing circuit is electrically connected to a first end of the receiving terminal signal processing circuit, a second end of the receiving terminal signal processing circuit is electrically connected to a second end of the signal transceiver circuit. The signal transceiver circuit transmits an uplink signal and receive a downlink signal simultaneously, and isolate the uplink signal from the downlink signal. In the above technical solution, the signal transceiver circuit may transmit the uplink signal and receive the downlink, and isolate the uplink signal from the downlink signal. It is able to achieve the self-interference suppression, and simplify a link.