Bismuth telluride (Bi2Te3) thermoelectric material is a functional material which can directly convert thermal energy and electric energy. It is widely used in solid state refrigeration, waste heat recovery and space power generation. At present, the research focuses in this field is how to improve the energy conversion efficiency of Bi2Te3 thermoelectric materials. In this paper, the research progress of Bi2Te3 based thermoelectric materials in recent years is briefly described, and the optimization of the thermoelectric properties of Bi2Te3 by nano-modification and doping modification methods is introduced, and the influencing mechanism is analyzed. The results show that the nano-structure and doping can improve the thermoelectric properties of Bi2Te3 to a large extent. Using Bi2Te3 based thermoelectric device, the flue gas waste heat recovery and utilization system of marine electric diesel engine is designed and simulated, and the power generation efficiency of the device is studied by building a test platform, which provides an experimental basis for the development of marine thermoelectric device. Finally, the development trend of Bi2Te3 thermoelectric material is prospected.