Launched from a sonobuoy tube and capable of autonomous flight, the autonomous sonobuoy frees the traditional sonobuoy from dependence on costly aerial delivery platforms. It can be installed on various small and medium-sized surface ships and unmanned vehicles to support the operational needs of long-distance and rapid situation awareness regarding underwater battlefields. By introducing the development of in-tube launch and sonobuoy technology, this paper proposes the design method of the autonomous sonobuoy and summarizes the key technologies of autonomous sonobuoy cluster operations, including cluster control, intelligent decision-making, network detection and so on. Furthermore, the combat patterns of autonomous sonobuoy clusters in wide-area cooperative detection, multi-source information support and evaluation assistance of combat effectiveness are analyzed. The results can provide references for the demand analysis, design and application of autonomous sonobuoy clusters.