In this study, three water gradients and four inoculation treatments were established to analyze the effects of a double inoculation of arbuscular mycorrhizal fungi (AMF) and rhizobia on the growth of Alhagi sparsifolia and nitrogen between the donor and recipient plants. The water gradient included normal water (soil relative water content (70±5)%), drought stress (soil relative water content (20±5)%) and rewatered treatment (return to the water content after 60 days of drought stress). The plants were inoculated singly with AMF or rhizobia. In addition, other plants were inoculated with both organisms (double AMF+rhizobia inoculation), and there was a control of no inoculation. The infection rate of AMF, the aboveground, belowground total biomass and the nitrogen content of double inoculation treatment was higher than that of the single inoculation when there was a normal amount of water. The nodule number, Fm, Fo and Fv/Fm did not differ from those of the single inoculation treatment. However, the AMF infection rate, total biomass and Fv/Fm rate of the double inoculation treatment were all lower than those of single inoculation under drought stress. There was no difference in the aboveground and belowground biomass, nodule number, Fm, Fo and nitrogen content compared with the single inoculation under drought stress. After rehydration, the aboveground, belowground and total biomass and the number of nodules on A. sparsifolia that had been treated with both AMF and rhizobia were higher than those inoculated singly. The rates of infection and nitrogen content rate of AMF after rehydration were lower than those that followed a single inoculation. The values of Fm, Fo, Fv/Fm did not differ from those of the single inoculation. An analysis of the amount of nitrogen transfer indicated that there was no difference between double and single inoculation under normal water conditions. However, the growth of A. sparsifolia that had been double inoculated decreased significantly under drought stress and could not be restored even after rehydration. It was apparent that the double inoculation of AMF and rhizobia compared with their single inoculation provides more benefits when the water content is normal and that drought stress will weaken the ability of AMF and rhizobia to synergistically enhance plant growth. After rehydration, A.sparsifolia that had been treated with both species quickly responded to changes in the water content. This ability can somewhat compensate for the effects of drought stress. However, it still cannot offset the damage. Arbuscular mycorrhizal network promoted nitrogen transfer and increased drought tolerance of A. sparsifoliaseedlings to a certain extent. However, the nitrogen transfer rate of double inoculation was lower than that of the single inoculation of AMF under drought conditions, which could not be reversed after rehydration.