In recent years,underwater acoustic(UWA)communication technology has been widely used in military marine environment observation. However,it is foreseeable that in the future,the UWA communication network based on half-duplex(HD)system can not meet the growing demand of underwater information interaction. In-band full-duplex(IBFD)UWA communication technology can transmit and receive communication signals in the same passband at the same time,which can double the efficiency theoretically. It has great research significance and application value under the background of severely limited spectrum resources of available UWA channel and rapidly increasing demand for underwater information interaction. Therefore,IBFD-UWA communication technology has gradually become a research hotspot in the field of UWA communication. This paper briefly introduces the current research status of IBFD technology under the background of radio and UWA communication,and discusses the main challenges faced by IBFD-UWA communication. Combined with existing research results and difficult problems in practical engineering application,several feasible research directions are proposed.