In a method for controlling an unmanned aerial vehicle (UAV), a digital image is obtained by an image capturing device of the UAV. The method detects an object in the digital image, determines a distance between the detected object and the UAV, and obtains a flight direction of the UAV if the distance is less than a preset value. The method further calculates a relative position and a relative angle between the detected object and the UAV, determines a flight limiting range of the UAV according to the relative position and the relative angle, and controls the flight direction of the UAV according to the flight limiting range.