Drought and heat tolerance are increasingly important agronomic traits. This study examines the mechanisms utilized by common desert species to adapt to drought, heat, and higher light intensity. Plants of four different families (the sandy shrub Salix gordejevii, the sub-shrub Artemisia halodendron,the legume Melissitus ruthenicus,and the sub-shrub Salsola collina) were grown in three different natural arid environments: Kerqin Sandy Land (least extreme heat and drought), Hulunbeier Sandy Land, and Songnen Sandy Land. The activities of the antioxidant enzyme systems superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) and the levels of malonaldehyde (MDA), a biomarker for oxidative stress, and the osmoregulatory substances soluble sugar and proline were monitored in leaves on a daily basis. No significant differences between environments for a single species were observed although antioxidantive enzymatic activities and osmoregulatory contents were somewhat lower in plants grown in Kerqin Sandy Land than in the more severely arid conditions found in Hulunbeier Sandy Land and Songnen Sandy Land. There were, however, significant differences between species. Melissitus ruthenicus had the highest POD and CAT activities and also the highest levels of proline and MDA; Salix gordejevii had the highest SOD activity and soluble sugar content and higher than average MDA content. Artemisia halodendron and Salsola collina had the lowest levels of proline and soluble sugar and activities of POD, CAT, and SOD, and a lower content of MDA. These results indicate that the degree of lipid peroxide is positively correlated with the activities of antioxdant enzymes and contents of proline and soluble sugar in these four species. However not all antioxidant enzymes increase uniformly among the four species in response to drought, suggesting that different antioxidant enzymes may be more important for imparting adaptation to arid conditions in some desert species as compared to others. In natural desert environments, Melissitus ruthenicus maintains its water balance and superoxide free radical metabolism balance by keeping higher concentrations of proline and activities of POD and CAT; Salix gordejevii by holding higher contents of soluble sugar and higher SOD activity; and Artemisia halodendron and Salsola collina by having leaf blades with a special structure to reduce taking in light radiation and avoiding water transpiration. These results suggest several different gene systems could be targeted for increasing drought tolerance in plants of economic importance.