[Objective] We aimed to sort out condition of soil moisture which is fitted for the growth of Reaumuria soongorica seedlings in arid or semi-arid area, and further provide a support for the preservation and reestablishment of Reaumuria soongorica population, and for the restoration of its community.[Methods] Pot experiment was carried out to study the effects of soil water limited stress on the growth of Reaumuria soongorica seedlings and the regulation of osmotic substances.[Results] Stem and leaf biomasses of Reaumuria soongorica seedlings were significantly decreased with the increasing of soil water limited stress, and seedling height also decreased gradually. Whereas, root-shoot ratio, root length and root surface area gradually increased. Root biomass experienced a decrease at light stress, and began to increase at server stress. Proline contents of stem-leaf and root in Reaumuria soongorica seedlings significantly increased with the increasing of soil water stress. However, changes of soluble sugar and protein contents in Reaumuria soongorica seedlings were not obvious.[Conclusion] Reaumuria soongorica seedlings have its adaption ways to drought through employing seedling growth adjustment, biomass reallocation, increase of root-shoot ratio, and accumulation of proline.