Two field experiments were conducted at Rice Research and Training Center (RRTC), Sakha Kafr El-Sheikh, Egypt, in 2010 and 2011 rice seasons to study the performance of SK2034H (H₁) and SK2046H (H₂) hybrid rice varieties under seeding rates i.e. 34, 46, 58 and 70 g/m² and N-levels (0, 50, 100, 150 and 200 kg/ha).                 The obtained results revealed that, in nursery studies SK2034H surpassed SK2046H in both seedling length and shoot length. On contrast the opposite results was observed with both number of leaves/seedling and root : shoot ratio. Seed rate of 34 and 46 g/m² gave the greatest seedling characters in nursery (greatest seedling vigor) compared with the other seed rates. SK2034H gave the highest number of leaves/seedling under 34 g/m², while SK2046H produced the greatest value in this aspect under both 34 and 46 g/m². The first three seed rates (34, 46 and 58 g/m²) improved root/shoot ratio of SK2034H, while the second hybrid responded to only 34 g/m².                 In the permanent field, SK2046H (H₂) hybrid had higher dry matter content (DM), leaf area index (LAI), flag leaf area (FLA) and root dry weight than SK2034H (H₁). Seed rate of 34 g/m² gave the highest previous growth characters than the other rates under study. The application of 200 kg N/ha gave the greatest values in the same growth parameters. Seed rate of 34 g/m² combined with 200 kg N/ha produced the greatest dry matter content and flag leaf area of SK2046H.                 In both seasons, H₂ surpassed H₁ in no. of panicles/m², 1000-grain weight, harvest index (HI) and grain yield. While, H₁ surpassed H₂ in both panicle weight and no. of filled grains/panicle. Seed rates of 34 g/m² was the best for number of panicles/m², yield components, while grain yield and HI was the highest under both seed rate of 34 and 46 g/m². Adding 200 kg N/ha produced the greatest grain yield and its components. Number of panicles/m² and 1000-grain weight of SK2046H (H₂) reached to maximum value under seed rate of 34 g/m² with 200 kg N/ha. Filled grains/panicle reached to the highest value when SK2034H (H₁) variety under the seed rate of 34 g/m² and fertilized by 200 kg N/ha. Grain yield of both hybrids (H₁ and H₂) was the best under the seed rates of 34 and 46 g/m² combined with 200 kg N/ha. The same trend was obtained with harvest index (HI).