This research aims to determine the types of gene action that control yield and its components in two crosses of bread wheat so that wheat breeders can select the most appropriate breeding approaches. The six-generation model is the best model for estimating the additivity of genes and deviations from additivity, including epistasis. Therefore, this research was done at Sids Agricultural Research Station, ICARC-WIP Project, throughout the three growing seasons, 2018/2019, 2019/2020, and 2020/2021, to determine heterosis, gene action, and mean performances, as well as inbreeding depression for grain yield and yield components. In addition, six populations (for the two crosses were produced from Gemmeiza 12 × Sids 14 and Misr 3 × Misr 1. Six parameters were estimated. In both crosses, the mean effects for all investigated characteristics are extremely substantial, demonstrating that these traits are quantitatively inherited. In the 1^st cross, inbreeding depression was found to be signifcant and positive for all characteristics, except for the 100-kernel weight. In the two crosses, potency ratio values were more than unity for number of grain spike^-1. The possibility of developing hybrid cultivars for plant breeders was examined in self-pollinated crops, such as bread wheat. Therefore, the exploitation of heterosis in various crops in the world has substantially increased human food or livestock feed production.