It is an unconstrained UAV benchmark focusing on complex scenarios with new level challenges.Selected from 10 hours raw videos, about 80, 000 represen-tative frames are fully annotated with bounding boxes as well as up to 14 kinds of attributes (e.g., weather condition, fying altitude, camera view, vehicle category, and occlusion) for three fundamental computer vision tasks: object detection, single object tracking, and multiple object tracking.