The present investigation was conducted at the Agricultural Research Station, El-Gemmeiza, Egypt, during the two winter seasons of 2014/2015 and 2015/2016. A half diallel cross analysis was made among eight parental bread wheat cultivars to study mean squares, mean performance and combining ability for days to heading, days to maturity, number of spikes/plant, number of grains/ spike, 1000-grain weight, grain yield/plant and protein content. The parents and F 1 crosses were grown in a randomized complete block design with three replicates and were sown under two sowing dates i.e., 20 th November (normal sowing date) and 20 th December (late sowing date). Mean square due to parents, F 1 crosses as well as general combining ability (GCA) and specific combining ability (SCA) were highly significant for all studied characters under both sowing dates. The ratio of GCA/SCA variance was more than unity for each of days to heading, days to maturity, number of spikes/plant, number of grains/spike and protein content under the both sowing dates as well as 1000-grain weight under the late sowing one. Otherwise, it was less than unity for 1000-grain weight under the normal sowing date. Moreover, GCA/SCA ratio was near to unity for grain yield/plant under the two sowing dates. The parental wheat cultivar Gemmeiza 12 and F 1 crosses (