Abstract: A flight control system of an unmanned aerial vehicle with differential positioning based on a CORS network includes a MEMS sensing unit for collecting data of angular velocity, linear velocity, air pressure, and magnetic field; a GNSS positioning unit for acquiring GNSS positioning data; a network communication unit for acquiring CORS differential data; an attitude/navigation control unit for controlling the attitude and navigation of the unmanned aerial vehicle, a main control unit for performing data processing, data fusion and system control operations among functional units. The 3G mobile network is used to obtain the differential data from CORS base station and realize an RTK differential positioning of the flight control system, which can satisfy the requirements of centimeter-level positioning accuracy of unmanned aerial vehicles for high-end consumer market and professional surveying and mapping.