During the summer growing season of 2021, seven elite yellow maize inbred lines were crossed in a half-diallel mating design at Gemmeiza Research Station. The resulting21 F1 crosses plus two check hybrids i.e., SC168 and SC3444 were assessed at three Agricultural Research Stations, Gemmiza, Ismailia and Sids, using a randomized complete block design (RCBD) with three replications in 2022 summer growing season. Data were recorded on number of days to 50% silking, plant height, ear height and grain yield. Mean squares owing to locations (L), crosses (C) and their interaction (C×L) were significant (P ≤ 0.01) for all traits under study. The mean squares resulting from general combining ability (GCA), specific combining ability (SCA) and their interactions with locations were significant for most traits under study. Both additive and non-additive gene effects were important in the inheritance of traits under study. However, additive gene effects were more important in the inheritance of most studied traits. The best inbred lines for GCA effects were Gm97 and Gz666 for grain yield. Compared to the checks; the three hybrids (Gm97 × Gz666), (Gz666 × Gm1002) and (Gm19 × Gm97) showed high grain yield and earliness. These hybrids could be used in the National Maize Breeding Program.