The objective of this investigation was to determine the combining ability for yield and its components in sunflower Aline by tester matting design among seven cytoplasmic male sterile lines and five restorer lines were selected to product 35 crosses. Parents and crosses were evaluated during the summer of 2017 year. Results indicated that the mean squares due to parents, crosses, parent's vs crosses except for days to 50% flowering and number of seeds plant -1 . Lines, testers, and line x

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... r were significant for all studied traits. A14 and A31 of A-lines and Rf1 and Rf20 of Rf testers proved to the best general combiners for seed yield plant -1 and the most of its attributes. Moreover, the best cross combinations were of A4 × Rf14, A6 × Rf14, A31 × Rf8, A28 × Rf20, A23 × Rf20, A1 × Rf1 and A14 × Rf11 that performed better than other developed hybrids in the view of seed yield plant -1 and one or more of its attributes. The ratio of σ 2 GCA/σ 2 SCA was less than unity for all the traits indicating that non-additive gene effects played an important role in the inheritance of these traits. The biplot graphic allowed a rapid and effective overview of general combining ability (GCA) and specific combining ability (SCA) effects of inbred lines, best lines, and testers as well as their performance in crosses.