Compared with drought stress, our knowledge about the potential precipitation increase in desert steppes and its ecological effects is still limited. In order to improve our understanding of the responses of desert steppe plants to climate change and human activities, we performed a 3-year-long controlled water addition experiment in grasslands with different grazing systems. The results showed that increased water changed the plant height/above-ground biomass/leaf-tissue thickness of Stipa breviflora Griseb., Cleistogenes squarrosa (Trin.