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As an indicator for terrestrial paleovegetation, the stable isotopic composition of total organic matter (delta C-13(org)) in loess sediments has been widely used for paleoclimatic reconstruction in western Europe, the Great Plains of North America and the Chinese Loess Plateau (CLP). However, little is known about the variation and paleoclimatic significance of the loess delta C-13(org) in arid Central Asia (ACA). We report delta C-13(org) data from an Axike (AXK) loess/paleosol profile from the eastern Ili Basin, eastern Central Asia. Along the profile, the delta C-13(org) values were more negative in the paleosol layers observed in the field and were confirmed by environmental magnetic proxies and a higher concentration of total organic carbon (TOC), consistent with results for western Europe and the northwestern CLP. Our results demonstrate that the loess delta C-13(org) in this region documents mainly the response of delta C-13 of locally predominant C-3 plants to paleoclimatic variation, especially paleoprecipitation. Our results also suggest that the loess delta C-13(org) values in the area have the potential for quantitative paleoprecipitation reconstruction on the basis of detailed delta C-13(org) results from modern plants and surface soils in the future. (c) 2013 Elsevier Ltd. All rights reserved.