The source of dust over the Tibetan Plateau is an important issue in the field of the plateau environment and climate. Previous studies have found that dust over the plateau comes from local release and transport by external deserts， but there are still deficiencies in quantitative analysis and sensible heat analysis of external deserts and seasonal contribution of dust over the plateau. In this paper， WRF-Chem （Weather Research and Forecasting coupled with Chemistry） is employed to study the seasonal distribution and transport of dust over the Tibetan Plateau and surrounding areas. The results show that the dust column loading seasonal variation trend is consistent with sensible heat in the dust source areas. Dust released by East Asian deserts （Gurbantunggut Desert， Taklimakan Desert， Gobi Desert） and South Asian desert （Thar Desert） accounts for more than 80% of total dust aerosol over the Tibetan Plateau. Dust released by The Taklimakan Desert contributes the most to the dust over the Tibetan Plateau in each season， at 40%. The contribution of Thar desert to plateau dust in spring and summer is relatively significant （about 25%）.