This study was designed to investigate the effect of applied some engineering parameters, such as three different level of ambient temperature (25, 30, and 35°C), and three different levels of nutrient irrigation flow rates (10, 15, and 20 l.hr-1), and three different plant densities (1, 2, and 3plant.pot-1), on some productive and vegetative characters for a variety of eggplant, (Solanum melongena L. Eggplant) in hydroponic system. In addition, water uses efficiency (WUE), the power requirements (PR), specific power (SP), and costs were determined. The results showed that, the best results under this variety of eggplant were obtained at ambient temperature average 30°C. It gives a total yield of 24.32 kg.m-2, consumed total power of 1360.11W, with SP of 55.93 W.kg-1, with WUE of 58.83 g.l-1, and total costs of 5.65 LE. kg-1. The optimum nutrient irrigation flow rate for the eggplant was about 10 l.hr-1. Which gives a total yield of 21.74 kg.m-2, consumed total power of 1360.11W, with SP of 62.56 W.kg-1, with WUE of 52.55 g.l-1, with total costs of 6.32 LE.kg-1.The plant density 3 plants.pot-1 was the best treatment for the same variety of eggplant. Which gives a total yield of 20.81kg.m-2, consumed total power of 1360.11watt, with SP of 65.36 W.kg-1, with WUS of 41.57 g.l-1, and total costs of about 6.61 LE.kg 1.