Twenty five new yellow maize inbred lines were top crossed with two testers, i.e. inbred lines; Sk11 and Gz658 during 2016 season at Sakha Agric. Res. Station of Agricultural Research center (ARC), Egypt. The resulting 50 crosses along with two commercial check hybrids ( SC 162 and SC 168) were evaluated in yield trails using a randomized complete block design with four replications at Sakha and Mallawy Agric. Res. Stations (ARC) in 2017 growing season to study the combining ability of these new inbred lines and evaluated the superiority of  crosses compered to commercial crosses. Mean squares due to hybrid (H),  hybrid × location  (H ×Loc.)  were highly significant for days to 50% silking, ear position, number of ears/ plant and grain yield/ha. Also, mean squares due to line (L), tester (T) and their interaction (L × T)  were significant for all studied traits except for  L×T of ear position, number of ears/plant and grain yield. The best inbred line, that revealed desirable GCA effects were Sk5008/27 for earliness, Sk5010/57 for ear position, Sk5010/54 for No. of ears/plant,  and Sk5008/31 for grain yield. The best hybrid superiority relative to checks was exhibited by Sk5007/27 × Sk11 for earliness, Sk5010/44 × Sk11 for ear position, Sk5010/58 × Sk11 for No. of ears/plant and  Sk5008/31 × Gz658 for grain yield. The 25 inbred lines were classified into two different heterotic groups using HSGCA method for grain yield, group 1 (Sk11) included seven inbred lines and group 2 (Gz658) included seven inbred lines.