This work aimed to investigate seed germination and growth of five tree species under water stress conditions of arid zones. Two separated experiments were carried out to assess their seed germination and water stress tolerance. The first one studied the effect of four seed treatments, including scarification, soaking in water, soaking in ethanol and control with no treatment, on the germination of three species including Acacia arabica, Acacia farnesiana and Albizia lebbeck. The second one assessed water stress tolerance of Bauhinia variegate and Delonix regia under four water stress levels or irrigation intervals of 1, 2, 4 and 8 weeks under plastic house conditions. The obtained results showed the importance of seed treatment for seed germination where no germination was obtained from control. Scarification was the best seed treatment allowing the highest germination percentage and seedling growth compared to other treatments. The studied species varied in their response to seed treatments where Acacia arabica gave the best results. The studied irrigation intervals were effective for the discrimination between the tested species. The assessment of water stress tolerance showed a variability between Delonix regia and Bauhinia variegate where the first was found to be more tolerant than the last. D. regia fully survived under all stress levels however, B. variegate did not survived starting from four weeks of drought. Both studied species decreased their growth under stress but B. varaiegata was very susceptible. The obtained results showed the possibility of successful production of all the tested trees throughout simple seed treatment. D. regia and similar species could be also successfully cultivated under water stress. It could be of great interest to save water in arid zones and enrich them with such economically and ornamentally important trees.