Abstract:High-resolution grain size records from Maogou section in Linxia Basin were characterized with relative stable fluctuationfrom 29Ma and 7.4 Ma, and changes in several sedimentary facies responded to Tibetan uplift in some short intervals. At about 7.4Ma,aeolian dusts gradually entered into Linxia Basin, and input fluxes of aeolian dusts had two rapid increased phases respectively atabout 6.4Ma and 5.3Ma, suggesting that NW China drying climate began at 7.4 Ma and strengthened rapidly at 6.4Ma and 5.3Ma.Comparing of our records with the Tibetan uplift and global climatic records, we found that the gradual uplift of the Tibetan Plateauand global cooling, especially the onset of Arctic ice sheet, since about 9-8 Ma, may be the two important forcing mechanisms for thefast aridification of Asian inland