Mechenical Engineering is one of the earliest established disciplines in Tsinghua University. In 1932, the Department of Mechanical Engeering was established, comprising an Aeronautical Croup and an Automobile Teaching Group. In the late 1940s, the enrollment of the department was already the largest among all engineering departments in the university. After a nationwide restructuring of colleges and departments in 1952, the department was renamed as the Department of Machine Manufacturing, comprising 5 disciplines：Manufacturing Technology, Foundry Technology and Equipment, Forging and Pressing Technology end Equipment, Welding Technology and Equipment, and etall. graphy and Heat Treatmento In addition, on the basis of the original Power Machinery Teaching Group, the Department of Power Machinery was set up, having 3 disciplines: Thermal Electr. geeratig (changed later to Boilers), Gas Turbines, and Automobiles and Tractors. In 1960, the Department of Machine Manufacturing was divided into the Department of Precision Instruments and Machine Manufacturing and the Department of Metallurgy with 3 additional new disciplines: Optical Instruments, Precision Instruments, and Special Metallurgy and Materials. And a Division of Agricultural Machinery was established within the Department of Power Machinery with Automobiles as its main discipline. Three years later, the Department of Power Machinery was renamed as the Department of Power and Agricultural Machinery. In 1977, the Department of Metallurgy was renamed as the Department of Mechanical Engineering. In 1978, four groups, i. e. , Boilers, Gas Turboachinery (changed later to Thermal Turbines), Automobiles, and Internal Combustion Engines, were cobiped to form the Department of Thermal and Automobile Engineering, and the discipline of Boiler was changed into Thermal Power Engineering, In 1980, the discipline of Air-conditioning was integrated into the Department of Theral Power and Automobile Engineering. In the early 1980s, the Department of Precision Instruments and Machine Manufacturing was renamed as the Department of Precision Instruments and echanology. In 1988, the Department of Thermal Power and Automobile Engineering was divided into the Department of Thermal Engineering and the Department of Automobile Engineering. The former consists of the specialties of Thermal Power Engineering, Thermal Turbine (now Power Machinery Engineering), and Air-Conditioning, and the latter consists of the discipline of Automobile and Internal Combustion Engine. In January 1996, the School of Mechanical Engineering was established, which included the Department of Precision Instruments and echanology, the Department of Mechanical Engineering, and the Department of Automobile Engineering. In October 1998, in order to further promote interaction and combination of different disciplines, the Department of Engineering Mechanics and the Department of Thermal Engineering were incorporated into the School of Mechanical Engineering.