The invention discloses an unmanned aerial vehicle monitoring method and an unmanned aerial vehicle monitoring system for a dam burst scene. The unmanned aerial vehicle monitoring method comprises steps that an unmanned aerial vehicle with fixed wings flies according to a first preset airline, and a first scene image of dam burst is acquired; edge detection on the first scene image is carried outto acquire the submerging range and the breach coordinate of the breached dam; the number of the rotor unmanned aerial vehicles is determined according to the submerging range and the breach coordinate, and each rotor unmanned aerial vehicle is controlled to fly along a second preset airline corresponding to the rotor unmanned aerial vehicle, and a plurality of sub-scene images and scene videos ofeach breach are acquired; Finally, the plurality of sub-scene images are spliced to acquire the second scene image of the dam burst; the disaster information of the dam burst is acquired according tothe second scene image and the scene video of each breach. According to the invention, the disaster information can be rapidly and accurately acquired by the unmanned aerial vehicle remote sensing technology, and the requirements of timely emergency monitoring are satisfied.