A half diallel set among five genetically diverse bread wheat (Tnticum aestivum, L.) genotypes were done in 2001/2002 growing season, The F1's of the ten crosses and the five parents were grown in a filed experiment at Giza experimental research farm, ARC next season (2002/2003), in a randomized complete blocks with three replications. Days to heading, Plant height, clays to maturity, number of spikes per plant, number of kernels per spike, 100-kernel weight, straw yield per plant, grain yield per plant and harvest Index were studied. The mean squares of genotypes, parents and crosses were highly significant for all studied traits. Positive heterosis over the better parent for three crosses for number of spikes/plant, one cross for straw yield per plant and one cross for grain yield per plant. Negative heterosis over the better parent was detected in four crosses for plant height, ten crosses for days to heading and one cross for days to maturity. The variances associated with general combining ability reached the level of significance for all studied traits except for harvest index. Specific combining ability was recorded for all traits except for grain yield. General combining ability variance was higher than the specific one for all characters except for days to maturity and 100 Kwt. Both types were of the same importance for days to maturity, while 100 kwt showed effects due specific combining ability. Four crosses were promising for early heading and/or early maturity. Also, several crosses were promising for improving grain yield plant