Two field experiments were carried out at Ismailia Agricultural Research Station in Ismsilia governorate during 2002/2003 and 2003/2004 growing seasons to study the effect of three nitrogen levels (30,45 and 60 Kg N/fed), three seeding rates (1.5,2.5 and 3.5 Kg seeds/fed) and two spacing between rows (25 and 50 cm) on growth, yield and yield components as well as seed oil content of canola (cv Serw 4) (Brassica napus , L.).                 Results over the two growing seasons revealed that : 1- Plant height, number of racemes and siliquas/plant, seed yield /plant, weight of 1000- seed, seed and oil yields /fed were significantly increased with increasing nitrogen level up to 60 kg N/fed. The opposite was true for seed oil content in both seasons.  2- Increasing seeding rates significantly decreased plant height, number of racemes and sliquas /plant ,seed yield/plant, weight of 1000-seed and seed oil content. Seed and oil yields /fed were maximum at seeding rate of 2.5 Kg/fed, followed by 3.5 Kg/fed. The lowest seed and oil yields/fed were obtained when seeding rate 1.5 Kg /fed in the two  seasons. 3- Increasing  row spacing from 25 to 50 cm resulted in significant increases in all studied characters, except seed  oil content in the two seasons. 4- In both seasons the interaction effect between nitrogen levels and seeding rates had significant on plant height ,seed yield/fed, seed oil content and oil yield/ fed ,while number of racemes /plant significant in the second season. The interaction effect between nitrogen levels and row spacings had significant on plant height in both seasons and number of racemes/plant in the first season .Also the interaction effects between seeding rates and row spacings had significant on number of racemes/plant in the first season ,seed yield/plant and seed oil content  in the second season. The highest values of seed and oil yields/fed were obtained when canola plants grown at 2.5 kg seed/fed in rows 50 cm apart and received 60 kg N/fed.  5- Simple correlation among studied characters revealed that seed yield/fed was positively and significantly correlated with plant height , number of racemes and siliquas /plant , seed yield/plant, 1000-seed weight and oil yield /fed in both seasons. Seed yield /fed was significantly and negatively correlated with seed oil content in the two seasons .