ABSTRACT: Diallel crosses, without reciprocals, among seven new yellow maize inbred lines derived from different maize populations were made in 2012 season at Giza Agric. Res. Station. The resultant 21 crosses along with two commercial check hybrids, i.e. SC 162 and SC 168 were evaluated in a randomized complete block design with four replications conducted at three locations, i.e. Sakha, Sids and Mallawy Agric. Res. Stations in 2013 season. The results indicatedthatmean squares due to GCA and SCA were highly significant for all traits studied, i.e. days to 50 % silking, plant and ear heights, ear length, ear diameter, No. of rows per ear, No. of kernel per row and grain yield per feddan indicating the importance of both additive and non-additive gene effects in the inheritance of the traits studied. The ratio of general to specific combining ability mean squares (δ2 GCA/ δ2 SCA) exceeded unity for all traits studied, indicating that the additive gene action was more important than non-additive gene action in the inheritance of traits studied. The parental inbred lines P1, P2, and P6 had significant positive GCA effects for grain yield. For other traits the best general combiner were P6 for earliness, and P3 and P4 for both shorter plants and lower ear placement. The best cross combinations for earliness were P1 X P4 and P4 X P6. Concerning plant and ear heights, the cross P3 X P5 had the shortest plants with the lowest ear placement. The cross P4 X P6 had the best SCA effects for grain yield. The crosses P1xP2, P2xP6 and P5xP6 significantly outyielded the check hybrid SC 168. These promising crosses may be released as commercial hybrids by maize research program after further evaluation.