Water stress (WS) is a significant abiotic factor that limits plant growth and development, especially in arid and semi-arid regions. The Argan tree Argania spinosa (L.) Skeels, endemic to southwestern Algeria, exhibits remarkable adaptation to drought conditions through various morpho-physiological and biochemical mechanisms that confer tolerance to WS. These characteristics position it as an ideal candidate for combating erosion and desertification, which are critical threats in arid and semi-arid areas. This study aimed to characterize the Argan tree from a morpho-physiological and biochemical perspective under WS conditions to evaluate its tolerance level to water scarcity and establish its threshold for potential introduction into the drylands of Algeria as a means of combating land degradation through restoration efforts. The results indicated that WS had a highly significant effect on all plant morpho-physiological and biochemical traits studied. In terms of morphological parameters, severe WS levels of 20% and 10% of field capacity (FC) resulted in a significant reduction in plant height, a decrease in the number of leaves, a reduction in radial growth, and a decline in aerial biomass. Additionally, an increase in root length and a preferential allocation of biomass toward the root system were observed. The best morpho-physiological performance was noted in plants subjected to moderate WS (30% and 40% FC). Regarding physiological and biochemical parameters, there was a progressive decrease in relative water content, transpiration, and cell membrane integrity percentage, reaching minimal values under the most severe stress conditions (20% and 10% FC). Concurrently, a significant accumulation of osmolytes, such as glucose and proline, was detected, with this accumulation intensifying as the WS level increased. At moderate WS levels (30% and 40% FC), this solute accumulation was largely associated with active osmoregulation, indicating the implementation of drought tolerance mechanisms such as osmotic adjustment. This increase in solutes was accompanied by an improvement in water use efficiency, particularly pronounced at 30% and 40% FC. This study demonstrates that Argania spinosa possesses the ability to adapt both morphologically and physiologically to WS. These preliminary findings provide a foundation for further research to explore the plant's potential and confirm the feasibility of successfully introducing this resilient tree. Such an introduction would represent a positive step toward reinforcing the green barrier in this region and enhancing its socio-economic benefits.