In a typical desert-oasis ecotone of the Hexi Corridor, we examined the eco-physiological and individual morphological responses of artificial rain-fed Haloxylon ammodendron in different plantation ages (5, 10, 20, 30, and 40a) under different soil water stresses imposed by high evapotranspiration and limited precipitation. The results showed that the soil moisture in 100-120 cm and 180-200 cm decreased sharply with the increase of Haloxylon ammodendron plantation age, especially after 30-40 years, the soil moisture decreased from 3%-4% to 1%-2%. In the early stages of 5-20a, Haloxylon ammodendron could respond to the fluctuations of soil moisture by increasing the osmotic adjustment substances (i.e. soluble sugar and soluble protein) and chlorophyll content and decreasing the Malondiadehyde (MDA) content of leaves to maintain the photosynthetic capacity of young leaves. Meanwhile, the vitality of feeder roots in the 0-20 cm increased significantly to absorb soil water at shallow depths. However, from 30 to 40 years, the osmotic adjustment substance and chlorophyll content in Haloxylon ammodendron leaves significantly decreased with the increase of MDA content, indicating that the function of eco-physiological regulation failed. The morphological adjustments of Haloxylon ammodendron occurred when the soil moisture decreased to 1%-2% after 30-40 years through reducing the biomass of leaf, branches and stems to lower the values of transpiration water consumption amount. These results indicated that in the arid desert-oasis ecotone with annual precipitation about 100 mm, Haloxylon ammodendron could alleviate the stress of soil moisture through physiological responses when the soil moisture kept at 3%-4% at the early ages of 5-20 years; however, after 30-40 years when the soil moisture decreased to 1%-2%, Haloxylon ammodendron could lose the old leaves, branches and stem to keep a dormant state (fake death).