In the present investigation, three cultivars of lettuce (Balady, Dark Green and Great Lakes) were fertilized with 30, 60 or 90 kg N/fed. and sprayed 2 times with GA₃ at 0, 50 or 100 ppm. The height of Dark Green plants exhibited significant increase, whereas Balady plants gaved significant increase in plant fresh weight, number of leaves, seed yield/fed. and average weight of 1000 seeds. Great Lakes was the earliest cultivar and had the highest number of seed stalks and the maximal percentage of bolting plants.                 Increasing N levels significantly enhanced the plant height, fresh weight and number of leaves/plant. Application of 60 kg. N/fed. increased the percentage of dry matter of leaves and resulted in the highest percentage of bolting plants, seed stalks number/plant, seed yield/fed., weight of 1000 seeds and germination percentage of produced seeds. The seed oil percentage was also increased when the nitrogen application rate was raised. Balady seeds exhibited considerable increase in its oil content when fertilized with 90 kg N/fed.                 Using GA₃ at 50 ppm increased seed stalks number/plant, percentage of bolting plants, seed yield, weight of 1000 seed and germination percentage of seed. However, the seed oil percentage decreased with the application of GA₃.                 In general Balady plants fertilized with 60 kg N/fed. and sprayed with 50 ppm GA₃ produced the highest seed yield.                 The results also revealed that lettuce seed oil (Balady cv.) could supplement or substitute the conventional oil types in terms of its fatty acid composition and other physicochemical properties