Unmanned aerial vehicle (UAV) plays a great role in missions that are boring,in harsh environment and/or dangerous. Because of its characteristics of low cost, zero casualties and low cost-effectiveness ratio, it has made great achievements in modern wars. While artificial intelligence brings great changes to UAV, the reliability and security of system operation increasingly depend on the stable transmission and control of information in complex electromagnetic environment. The survivability, adaptability and even electromagnetic check and balance ability of UAV in harsh electromagnetic environment lead the development trend of electromagnetic attack and defense of information equipment to a certain extent. Therefore, this paper summarizes the electromagnetic environmental effect and electromagnetic protection technology of UAV, expounds the methods of UAV electromagnetic countermeasures and electromagnetic protection at the information level and energy level, expecting to realize electromagnetic attack and defense of UAV from the intelligent point of view.