Abstract: In order to solve the problem of global seamless tracking and monitoring of aircraft, a flight tracking and monitoring system based on positioning and communication function provided by Beidou Navigation Satellite System (BDS) is designed. A newly developed airborne BDS equipment with positioning and communication functions integrated is installed on aircraft by retrofit. The installed BDS equipment calculates the BDS position of the aircraft and acquires important aircraft parameters like flight number, on-board fuel quantity, etc. BDS position and the acquired aircraft parameters, which are packed according to a pre-designed protocol, are sent to user ground system periodically. The whole system, including positioning source, communication link and the receiving system on the ground, is fully independently self-controllable. Flight tests are conducted after retrofit, and test results show that the rate of successful communication meet expectation. Besides, BDS and GPS data collected from flight tests are exported and compared. Flight track generated by BDS and GPS show good consistency through comparison. The designed system has been delivered to airline users for daily use.