“Fuxing” Deep Sea Profile Buoy moves freely like stars floating on the water when a body of buoys work in the global ocean. It is a miniaturized and low-cost underwater mobile observation platform designed by Tianjin University. It can realize automatic adaptive balancing, fixed deep diving, hovering and buoyancy in any sea and obtain water parameters according to the type of sensors such as CTD, dissolved oxygen, ADCP and so on. It is an essential tool applied for marine scientific research.