The cooperative guidance and control technology is the underlying technical foundation for achieving behavior cooperation and complementary capabilities of all members in a swarm system and the boundary expansion of the overall system capability. This study focuses on unmanned system swarms such as the unmanned aerial vehicle (UAV) swarm and loitering munition swarm and describes the technical roles of the cooperative guidance and control technology in formation control, formation reconfiguration, robustness enhancement, cooperative attack, and route planning. In addition, we introduce the typical algorithms and research status of the above key technologies. Finally, we forecast the development trends of cooperative guidance and control in invulnerability, universality, denial adaptation, and multi-disciplinary optimization.