The unmanned aerial vehicle comprises an unmanned aerial vehicle main body, a storage cavity is formed in the unmanned aerial vehicle main body, and a plurality of rotor wing flight devices are arranged on the side surface of the unmanned aerial vehicle main body; a waterproof upper shell is arranged at the upper end of the unmanned aerial vehicle body, and a first waterproof sealing ring is arranged between the waterproof upper shell and the unmanned aerial vehicle body. An electronic element installation cavity with an upward opening is formed in the middle of the aluminum radiator in the storage cavity, the side face of the waterproof upper shell is an arc-shaped face, the upper end face of the waterproof upper shell is a plane, an automatic cable grabbing mechanical arm is fixedly arranged on the upper end face of the waterproof upper shell, and a thermal infrared imager, a camera and an ultrasonic flaw detector are fixedly arranged in the waterproof upper shell. The technical scheme is reasonable in structural design, simple in structure, easy to assemble and disassemble, good in waterproof performance, long in working time, convenient to use and capable of working normally under severe conditions such as rainy days and nights.