Maritime search and rescue (MSAR) is an important aspect of maritime traffic safety. Currently, China's MSAR system mainly relies on GPS or Beidou localization devices carried by persons in distress, as well as boats and helicopters, however, it has the following problems: Due to the limitation of ship height and speed, the scope of search and rescue operations will be greatly reduced. Moreover, the exact position of persons in distress cannot be received if the GPS or Beidou signal is interrupted. Considering the high efficiency and convenience of UAV, this paper proposes a scheme of MSAR system for persons in distress based on UAV, which is mainly divided into three modules: The first is the wireless location module, which mainly performs two-phase wireless location of the distress signal sent by the beacon on the persons in distress, and can obtain the search and rescue range of the target in the case of GPS or Beidou failure; The second is the drift track prediction module, taking into account the impact of ocean current on the location of persons in distress, and realizes the further search and rescue scope; Finally, the target detection module detects and identifies targets of persons in distress on the nearby sea. Through a series of simulation experiments, the proposed search and rescue scheme, integrating key technologies for MSAR, can effectively achieve the task of searching and rescuing persons in distress at sea, and has great research value and significance.