The Tibetan Plateau is an important member of the global climatic system. Researches on interdecadal climatic variations over the Plateau based on different substitute data are enumerated systematically and the research progresses on dry, humid, cool and warm features of the plateau environment and the variation of snow cover and heat sources (sinks) are listed in detail. It reveals that it is colder before the 1920s and warmer from the 1920s to the 1950s and after the 1980s. There are same changes occurred over the Tibetan Plateau in accompany with the worldwide warming jumping around the 1980s, which is earlier than that of the North Hemisphere. The precipitation and snow cover over the plateau tend to increase under the context of global warming. There are obvious regional and seasonal climate variations on the plateau. The thermal/mechanical forcing and terrain effect of the plateau and the impacts on the Asian monsoon onset, rainfall in monsoon regions, and regional and global climatic changes are analyzed. Some existing problems in the related researches and research priorities in the future are also discussed.