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Surface sands and sandstones in the Ordos region, alluvial sands from the surrounding mountains, and fluvial sands in the Yellow River are systemically collected for granulometric, mineralogical, geochemical and isotopic analyses. Fine-grained fractions are small for the Ordos desert sands as well as alluvial sands of the surrounding mountains whereas they are abundant for fluvial sands of the Yellow River. Quartz, feldspar and muscovite are common minerals but their relative proportions are variable for various sediments. REE grained sands vary significantly in the Ordos deserts. Based on the integrated Sr-Nd isotopic data, the possible geochemical compositions are roughly identical but isotopic compositions, particularly epsilon(Nd)(0) values of fine-grained areas are isotopically divided into four regions for fine-grained sands in the Ordos deserts: region A, the Helan-Yin mountain ranges; region B, the Ordos sandstone areas; region D. the Tarim Basin, the Alxa Plateau, the Hexi Corridor, the northern Qinghai-Xizang Plateau and the Yellow River drainage; and region E, the Jungger Basin and the southern Mongolia. Through geochemical and particularly isotopic comparisons in combination with expert meteorological and geographical knowledge, fine-grained sands in the Ordos deserts originated both from weathering of local sandstones and from blowing of fine sediments in region D. The input from region D is subordinate to the local source for fine-grained sands in the Ordos deserts. Contributions from weathering of local sandstones might be roughly homogeneous from the west to the east of the Ordos region as well as the input of fine-grained sediments from remote areas such as the Tarim Basin, the Qinghai-Xizang Plateau and the Alxa Plateau. Geographical Nd isotopic variations of fine-grained sands in the Ordos deserts might be caused by the input from adjacent places such as the Yellow River drainage due to the near-surface winds. (C) 2011 Elsevier B.V. All rights reserved.