The present invention relates to the unmanned aerial vehicle technology field, in particular to a binocular vision-based unmanned aerial vehicle obstacle avoidance method and system. The method comprises the following steps of obtaining an environmental image in front of an unmanned aerial vehicle via a binocular camera; according to the obtained environmental image, identifying whether a target object is in front of the unmanned aerial vehicle; if the target object exists, based on the current attitude information of the unmanned aerial vehicle and a depth value of the target object obtainedaccording to the environmental image, determining whether an obstacle exists in the front target object; if the obstacle exists in the target object, based on a target depth value, obtaining the distance between the unmanned aerial vehicle and the obstacle, and avoiding the obstacle according to the distance between the unmanned aerial vehicle and the obstacle; if the target object is just the ground, the unmanned aerial vehicle not adopting an obstacle avoidance measure. The binocular vision-based unmanned aerial vehicle obstacle avoidance method and the binocular vision-based unmanned aerialvehicle obstacle avoidance system provided by the present invention realize the function of effectively distinguishing the obstacle and the ground in a low-altitude flight environment, and avoid thephenomenon of taking the ground as the obstacle mistakenly during the flight to frequently hover.