Tamarix ramosissima and Haloxylon ammodendron are constructive species in the southern desert of Junggar Basin.The study compares the morphological and anatomical features of photosynthetic organs of Tamarix ramosissima and Haloxylon ammodendron in 4 kinds of desert habitats surrounding Karamay agricultural development region.The results show that Tamarix ramosissima adapts to the desert environment by its systematical evolution characters,ecological adaptation characters(in which cuticle thickness,palisade tissue thickness,epidermal cells thickness of leaf are contained),and special adaptability structures.Haloxylon ammodendron relies on its systematical evolution characters and special adaptability structures to adapt to the desert environment.Comparing the plasticity of photosynthetic organs of Tamarix ramosissima and Haloxylon ammodendron,different requirements for water and salt of the two plants have been found: Haloxylon ammodendron has wider ecological amplitude as well as better tolerance.When the soil water content ranges from 3.55% to 9.4%,and soil electrical conductivity ranges from 948.47 μs·cm-1 to 1 759.64 μs·cm-1,the habitats are good for Tamarix ramosissima.When the soil water content ranges from 0 to 3.93%,8.02% to 9.4%,and soil electrical conductivity ranges from 657.48 μs·cm-1 to 4 380.0 μs·cm-1,the habitats are good for Haloxylon ammodendron.