A rainfed field experiment was conducted from 1989-90 to 199-92 to evaluate the relative performance of promising Indian mustard [Brassica juncea (L.) Czernj, & Cosson] varieties under varying levels of nitrogen application. Yield attributes, viz. branches/plant, siliqua/plant, siliqua length, grains/siliqua and 1,000-grain weight showed the maximum expression in 'PR 45'. Variety 'PR 45' outyielded 'Kranti','Varuna' and 'Krishna'. This variety also showed maximum water-use efficiency, oil content, nitrogen content and its uptake in whole plant followed by 'Kranti'. However,'Krishna' appeared to be the least effective for seed yield, oil yield and water-use efficiency. Increasing levels of nitrogen significantly enhanced the seed yield, water-use efficiency, oil content and yield as well as nutrient content and uptake.