The invention discloses an unmanned aerial vehicle flight control system and control method, and belongs to the technical field of unmanned aerial vehicle flight control. The unmanned aerial vehicle flight control system comprises an information processing module, a power module, an information acquisition module, a data communication module and a control end, the information processing module is connected with the power module, the information acquisition module and the data communication module and performs data transmission and control on the power module, the information acquisition module and the data communication module, and the power module provides flight power for an unmanned aerial vehicle. The information acquisition module acquires external environment information and unmanned aerial vehicle attitude data information, the data communication module is connected with the unmanned aerial vehicle and performs data communication with the control end, the control end performs remote control on the unmanned aerial vehicle, and the information processing module processes data according to the data of the information acquisition module. According to the invention, multiple types of information are collected, and high-reliability support is provided for automatic route planning; and the system can realize full-angle sensing, can avoid obstacles in time, can cope with navigation in narrow or channel environments on the two sides, and improves controllability and high applicability.