Marine buoy is an important part of underwater acoustic communication system. It is of great significance to track and locate it. It is widely used in ocean environment three - dimensional monitoring, underwater multimedia communication, underwater mobile carrier navigation and positioning, marine resources detection, remote control of submarine topography mapping and offshore oil industry, data acquisition, etc. This paper describes the application of the monitoring service of GPRS / GPS module at Marine buoy. It can achieve real - time location of underwater acoustic communication devices and route tracking to avoid the loss of the device, as well as assist to retrieve the lost device.