The present investigation was carried out during 2011 and 2012 summer seasons at Shandaweel Research Station Sohag .Eight genetically diverse sesame genotypes were used for this study. All possible crosses among parents, without reciprocals, were done to make a diallel series of twenty eight hybrids. A randomized Complete Block Design with three replications was adopted. the major objectives of this work are to estimate the genetic components for seed yield  studying the interrelationships among traits, using path coefficient and factor analysis to determine the important traits which can be used as selection criteria. The additive genetic component “D" was significant in all studied traits.  The dominance genetic components (H₁ and H₂) were significant in all studied traits except h₂ for plant height and seed yield\plant were insignificant .Moreover, the dominance component (H₁) was higher in magnitude than (D) component for all studied traits except 1000-seed weight, resulting in the average degree of dominance (H₁ \ D)^1\2 which was more than one indicating over dominance for all studied traits.