Based on NCEP/NCAR daily reanalyzed data from 1948 to 2011, the atmospheric heat sources in Asia are computed by the inverted arithmetic. Then the characteristics of pentad changes of heat sources over Indo-China Peninsula and Tibetan Plateau and the relationship between South Asia High's position and changes of heat sources over above-mentioned zones are analyzed. The results show that it is at pentad 12 when the atmosphere over Indo-China Peninsula shifts from a cold source to a heat one. The centre of the South Asia High moves over the Indo-China Peninsula when the thermal gradient decreases between Indo-China Peninsula and the adjacent areas on its east and west sides and the atmosphere over the Bay of Bengal, Indo-China Peninsula and the Philippine Islands all becomes heat sources. The centre of South Asia High moves over the Tibetan Plateau when the Tibetan Plateau heat source develops into its climax period. And the centre moves out the plateau when the atmosphere over the Tibetan Plateau turns cold. The Indo-China Peninsula heat sources trigger the westward movement of the South High. The entering and exiting of the South High over the Tibetan Plateau are influenced by the heat sourceś strength over the plateau and the changes of circulation.