Effect of irrigation with mixed sewage effluent water and fresh water on growth of casuarina, jatropha and khaya tree seedling was evaluated in new Minia city, Minia, Egypt from Jan. 2018 to Dec. 2019. The most studied characters showed significant response for species, water treatments and their interaction. Khaya tree seedling irrigated with the treatment 50% sewage water + 50% freshwater gave the highest plant height. Casuarina seedling irrigated with 50%s+50%f had the highest stem diameter and branches/plant, while those irrigated with 25%s+75%f gave the highest leaves/plant. Casuarina seedling irrigated with each of 100%s or 75%s+25%f gave the highest stem fresh weight and shoot fresh weight without significant difference. Moreover, the highest values for shoot: root ratio and stem dry weight were recorded for casuarina seedling irrigated with 75%s+25%f. Irrigation of jatropha seedling with treatment 100%s gave the highest values for each of branches fresh weight and leaves fresh weight, branches dry weight and leaves dry weight. Also, jatropha seedling irrigated with treatment 100%s and 50%s+50%f gave the highest leaves fresh weight without significant difference. Khaya seedling irrigated with the four water irrigation treatments had the highest chlorophyl B and carotenoids contents without significant difference.