Two field experiments were carried out at the Agricultural Research and Experimental Center, Faculty of Agriculture at Moshtohor, Zagazig University, during 2001/ 2002 and 2002 / 2003 seasons to study the effect of Bradyrhizobm inoculation , nitrogen fertilizer rates and foliar application with molybdenum on yield , its components and seed quality of lupin cv. Giza 1. Each experiment included 12 treatments which were the combination between two inoculation treatments (uninoculation and inoculation), three N rates (0 , 15 and 30 kg N/fed) and two spraying treatments with Mo ( tap water and 30 ppm). The obtained results of each season and the combined analysis of two seasons revealed that:- 1-Inoculated plants significantly surpassed uninoculated ones in number of nodules/plant , plant height , number of branches and pods / plant , seed yield/plant, 100- seed weight and seed yield/fed . Number of seeds/pod , pods weight/plant , seed N content % and seed protein content % were not affected by inoculation. 2-Adding nitrogen fertilizer to lupin plants caused an increase in all traits studied. Nitrogen fertilization at a rate of 30 kg N/fed increased seed yield/fed over unfertilized plants and that received 15 kg N/fed by 38.8 and 7.7 %, 35.4 and 6.7 % and 37.0 and 7.2 % in the first season, second season and combined , respectively. 3-Molybdenum application effect on all traits studied were significant in the 1st and 2nd seasons as well as combined analysis except plant height and seed yield/fed in the first season and number of seeds/pod in the 2nd season. 4-Inoculation x N rates interaction had significant effect on nodules number/plant, plant height, seed and protein yields/fed and N uptake/fed., while number of nodules/plant and seed yield/plant were significantly affected by the interaction between Mo spraying and N rate