The variations of δ13C and the contents of five pigments and proline in needles of S. przewalskii from Dahuoshao (dry site) and Tulugou (wet site) in the Qilian Mountains were investigated. The needles contain more δ13C,carotenoids, xanthophyll and proline,less chlorophyll,anthocyanin,rhodoxanthin and Fv／Fm in the dry condition. Except for Fv／Fm and chlorophyll, other examined parameters of mature trees are higher than that of young trees in both environments. These results suggest that the pigments play an important role for drought-induced photo-protective function,and the S. przewalskii species can acclimate to the arid environment in a long term by changing the pigment contents.