Abstract: Swarm intelligence is one of the important development directions of artificial intelligence. As one of the main forms of artificial swarm intelligence, unmanned system swarm intelligence has wide and important application prospects in many military and civilian fields. At the same time, it faces many challenges of basic theories and methods, core technologies and system construction. This paper firstly expounds the basic concept of swarm intelligence and presents a reasonable classification, and then analyzes its several main characteristics including self-organization, self-adaption, self-learning as well as self-emergence, discusses its current research status from two aspects including bionic swarm intelligence mechanism and classical unmanned swarm intelligence system instances, and fully summarizes its research characteristics according to four aspects including bionic mechanism, driving mode, research and development mode as well as system practice. Furthermore, this paper gradually and systematically combs and condenses the main research directions worthy of continuous deepening from three aspects including theories and methods, core technologies and system construction for unmanned system swarm intelligence and its systems, which hopes to be used for reference to relevant researchers.