The design and implementation of an underwater acoustic detection buoy is introduced. The buoy is based on Argo buoy of Beidou system,which carries underwater acoustic detection load,can sink and float independently in water,and can detect underwater acoustic communication signals. After discovering the target,it transmits the relevant characteristic information of the target through Beidou satellite. It can realize the functions of programmable floating,self-positioning,satellite communication,underwater acoustic signal detection and recognition,data recording,information display,etc. It can be widely used in underwater safety investigation of important waterways,exercise areas,etc. It can obtain the layout and distribution information of underwater acoustic communication network,and provide decision-making basis for important military operations of our forces.