Abstract: The key technology of unmanned aerial vehicle (UAV) data link has always been a research hot-spot in recent years, The air-space-ground communication network constructed by UAV data link plays an important role in both military and civilian fields.As an important part of UAV,the UAV data link is facing new requirements such as low detection, anti-interference, high transmission rate and high-reliability communication as the payload performance of UAV improves.This article introduces the technical composition and development trends of foreign advanced data link, conducts a survey of data links in UAV at home and abroad, briefly summarizes the key technologies required for the application of data links in UAV.