Stipa purpurea Griseb,the dominant species of alpine steppe,is widely distributed across the large precipitation gradient on the Tibetan Plateau. It is possible that because of local adaptation, 5. purpurea populations from different habitats along this precipitation gradient respond differently to drought, which may affect their responses to climate change. To explore the problem, in the present study, we investigated the physiological and molecular response of S. purpurea seedlings from two different populations (Pulan & Cuoqin) to 14-d drought stress and subsequent recovery. The results showed that the relative water content, chlorophyll fluorescence, content of osmoticant proline and malondialdehyde (indicator of oxidative stress),accumulation of reactive oxygen species,antioxidant enzyme activities and the expression of drought-related genes all changed under drought treatment and went back to the control levels in the subsequent recovery in plants from Pulan. However, these patterns were quite different in plants from Cuoqin, in which these traits changed by inconsistent degrees and did not return to pretreatment levels after rewatering. The results demonstrated that the plants from Pulan had greater resistance to drought stress compared with those from Cuoqin,which had a larger mortality rate ultimately. Combating the differences of offspring in response to drought and the habitat distribution of parents,we considered that genetic basis has been obtained in response to precipitation difference among S. purpurea populations. The results help to understand the adaptation and evolution of S. purpurea to the special environment and the effect of climate change to this botanical system.