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The Tarim Basin(TB in short)in northwestern China is one of the most arid regions in the middle latitudes,where water is scarce year round.This study investigated the variations of summer precipitation in TB and their association with water vapor fluxes and atmospheric circulation.Our results suggested that the variations of summer precipitation in TB are dominated by the water vapor fluxes from the south and east,albeit the long-term mean water vapor mostly comes from the west.The anomalous water vapor fluxes are closely associated with the meridional teleconnection pattern around 50-80°E and the zonal teleconnection pattern along the Asian westerly jet in summer.The meridional teleconnection connects the Central Asia and the tropical Indian Ocean; and the zonal teleconnection resembles the ―Silk Road pattern‖.The two teleconnections lead to negative height anomalies in the Central Asia and the positive height anomalies in the Arabian Sea/India and North Central China.The anomalous pressure gradient force,caused by these height anomalies,leads to anomalous ascending motion in TB,and brings low-level moisture along the eastern periphery of the Tibetan Plateau and water vapor from the Arabian Sea passing over the Tibetan Plateau to influence the precipitation development in the study region.