Field experiment was carried out at the Experimental Farm of the Salinity and Alkalinity laboratory, Sabaheia- Alexandria, to quantify growth, biomass and chemical composition on responses of lebbeck and chinaberry to three levels of drought stress and three organic amendments after two successive seasons of 2015 and 2016. The results indicated that well-watered treatment had the higher values of height growth, stem diameter, leaves number, shoots dry weight, shoots: roots (S: R) ratio, total chlorophyll and total carotenoides. On the other hand, severe treatment (50% field capacity) resulted in the highest values of roots dry weight, proline and total phenols contents for both tree species. Compost was better to enhance the growth parameters of lebbeck while, humate was the better to increase growth parameters of chinaberry. Total chlorophyll and total carotenoides of the two species were enhanced by adding humate. The interaction results indicated that the highest values of growth parameters of lebbeck resulted from compost combined with moderate or well-watered treatments. While humic acid combined with well-watered or moderate treatments were the best for growth of chinaberry seedlings.