Modern science and technology put forward new requirements for accurate measurement of local temperature in various occasions, which greatly promotes the development of temperature sensor. Due to the advantages of passivity, short response time, high accuracy and little impact on the testing environment, thin film thermocouples have broad application prospects in the field of temperature measurement. The work summarized the research progress and hotspots of thin film thermocouples in recent years. Firstly, the structure of thin film thermocouples based on different materials was presented. Then, metal, ceramic and composite thin film thermocouples and common electrode materials used in high temperature measurement of aero-engine hot end components were introduced respectively. The effects of thickness of film, annealing treatment, type of electrode film, atmosphere and doping on thermoelectric potential, Seebeck coefficient, high temperature resistance and microstructure of electrode of thin film thermocouples were discussed. The typical research results in recent years were summarized, and the advantages of ceramic thin film thermocouples for temperature monitoring in aero-engine were described. In addition, the development course, structure optimization design, research and improvement of fabrication technology and the layout in real temperature measurement occasions of thin film thermocouples array applied to local two-dimensional temperature field measurement were analyzed and discussed. Finally, the research and development direction of the thin film thermocouples in related application fields are prospected.