A complete diallel cross among six new yellow maize inbred lines , i.e.  10RF , 11RF , 39RF, 45RF , 48RF and 50RF (Developed Improvement of Maize by Industrial Genotype  Project) was made in 2010 summer season .Parental inbred lines and F₁  crosses along with two yellow commercial check hybrids, SC155 and SC162 were evaluated in randomized complete block design with four replications at Gemmeiza in two different dates ; 15 April and 15 may 2011 summer season to  study the combining ability in order to identify the most superior parental inbred lines that produce superior hybrids and develop high yielding new yellow single crosses. Results indicated that  general combining ability (GCA) were highly significant for plant and ear heights , specific combining ability(SCA) were highly significant for grain yield (ardab / feddan) and a significant for days to 50 %  silking .The non-additive genetic effects were more important and played the major role for all traits inheritance of. Generally most of F₁ single crosses were earlier , shorter and had lower ear placement than two checks hybrids ; SC162 and SC155 . All the F₁ crosses were resistance to late wilt disease. All the F₁ crosses out yielded significantly better than the check SC162 , except four crosses . Single  crosses (P₄×P₁) was significantly better than the best check SC155 for grain yield ,shorter for plant height and earlier in days to 50%silking  , however there were seven single crosses, i.e. (P₅×P₄ ), (P₄×P₂), (P₁×P₄) , (P₁×P₅), (P₂×P₃), (P₆×P₁) and (P₂×P₆)which statistically equal the check cross 155 and significantly earliness, shortens and lower placement ear; in addition those crosses yielded better than the best check hybrid insignificantly   P₁ (10 RF) was good combiner for resistance to late wilt disease and grain yield(ard/fed) . However P₄ ( 45 RF ) was good combiner towards shortness, low ear placement and late wilt disease  resistance. For (SCA) effects of the 15 F₁ crosses had positive and highly significant effects . However for maternal effect or reciprocal (SCA) effects were found that single crosses i.e, ( P₅ × P₄ ), ( P₃ × P₆ ),       ( P₄ × P₂ ),( P₅× P₃ ),( P₁ × P₃ )  and ( P₆ × P₁ ) yielded highly significant for grain yield of 32.7 , 31.83 , 32.52 , 30.93 , 30.42 and 31.28 (ard/fed) relative to its reciprocal parents , respectively. Therefore , these crosses may be released as new high yielding single crosses.