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For the mechanistic understanding of hydroclimate variability, stable oxygen isotopic ratios (delta O-18) of tree-ring alpha-cellulose can play a key role in paleoclimatic research. On the north-east Tibetan Plateau (TP), a region particularly sensitive to climate change, there exists a distinct lack of delta O-18 research in tree-ring archives. The few currently existing tree-ring delta O-18 chronologies were obtained by pooling the wood material from the same year from different trees prior to preparation and analysis. Although this method is time and cost efficient, it might impede the analysis of changes within the internal variability of oxygen isotope signals and a deeper understanding of the resulting climate reconstruction. We selected five Qilian juniper (Sabina przewalskii Kom.) trees covering the period 1951-2011 on the north-east TP to investigate the climate signals contained in stable oxygen isotopic composition records obtained using single tree analysis. Although the inter-series correlation between the five individual delta O-18 series indicates a highly significant relationship (mean r = 0.59, n = 59, p = 0.01), the five individual delta O-18 series show significantly differently mean values. We found significant negative correlations between drought/hydroclimatically triggered climate parameters (PDSI, precipitation) and each of the individual delta O-18 series. Spatial correlation maps indicate negative correlation of tree-ring delta O-18 and Indian Ocean sea surface temperatures, and inverse correlation patters of moisture conditions on the northern and southern TP. Our results provide a reference for future research on stable oxygen isotope/climate signals in the species S. przewalskii Kom.. (C) 2014 Elsevier B.V. All rights reserved.