A two-year field experiment was conducted at the Agricultural Research Station of Giza, Agricultural Research Center, during the two growing seasons of 2006/2007 and 2007/2008. The experiment was carried out to study the effect of four levels of N fertilizers i.e 0, 40, 80 and 120 N kg/fed on yield and some of its components of some wheat cultivars namely: Sakha 94, Gemeiza 9 and Giza 168. Also, to investigate the relationship between grain yield and its components using some multivariate procedures i.e correlation, path-coefficient and stepwise multiple linear regression. The results cleared that Gemeiza 9 cultivar surpassed each of Sakha 94 and Giza 168 cultivars in number of spikes/m2, number of spikelets/spike, weight of 1000 grains, biological and grain yields in both seasons of the study. Increasing N fertilizer to 40, 80, 120 Kg N/fed significantly increased wheat yield and its components. The highest values of yield and its components were obtained by applying 120 Kg N/fed. The interaction of wheat cultivars and N fertilization significantly affected spike length, biological and grain yields only in the first season. The results of multivariate analysis procedures revealed that number of spikes/m2, number of grains/spike and weight of 1000 grains were the most important contributing characters in the total variability of grain yield. These characters have to be ranked the first in any breeding program to improve wheat grain yield.