One-year-old seedlings of Tamarix ramosissima Ledeb. and Alhagi sparsifolia Shap., two dominant species in the southern rim of the Taklamakan Desert, were investigated. A root uprooting and trench profile method were used to study the characteristics of the biomass distribution and root architecture. The results showed that the biomass distribution of two species differed. T. ramosissima had more biomass in the shoots, whereas A. sparsifolia had more biomass in the roots. The root architecture of two species differed, the root distribution of T. ramosissima resembled a “herringbone” formation in vertical profile, whereas the roots of A. sparsifolia were distributed in the form of a web, with dichotomous architecture.