A mobile terminal and switching method for controlling data transmission interface thereof are provided. The mobile terminal includes an application processor, a communication processor and data transmission interfaces thereof, the application processor including a traffic monitor unit and an interface control unit, wherein the traffic monitor unit is configured to detect data traffic of data transmission, compare the data traffic with a preset threshold to obtain a comparison result, and output the comparison result; and the interface control unit is configured to control, on receipt of the comparison result, the connection or disconnection of a high-speed data line between the application processor and the communication processor, and to transmit a corresponding interface switching command to the communication processor for switching the data transmission interface. With the present system, the power consumption of the system can be reduced and the efficiency of the data transmission can be improved.