D ROUGHT stress is a serious abiotic stress affecting crop production in Egypt. The aim of this article was to study the gene action controlled seed cotton yield (SCY/P) and fiber properties under normal irrigation and water deficit conditions. Ten cotton genotypes (G. barbadence L.) were crossed as lines to three as testers. The parents and hybrids were evaluated in a randomized complete block design with three replications under normal and water deficit at the Agriculture Research Center, Sohag Governorate, Egypt. The two hybrids [G95 ˟ (G90 ˟ Aust.)] and [Aust. ˟ (G90 ˟ Aust.)] were the best hybrids for most studied traits and should be considered in breeding program for drought stress and normal irrigation, and the parents G.95, (G95 ˟ Aust.) and Aust. depicted their good combining ability. Mean reduction % of the parents varied greatly from 2.99 for lint % to 31.79 for SCY/P, while it varied for the hybrids from 5.11 for fiber strength to 33.93 for SCY/P. The additive (σ 2 A) and the dominance variance (σ 2 D) were larger under normal irrigation than under water stress conditions for most traits. The ratio σ 2 A/σ 2 D was less than unity for all traits indicating that the role of dominance was more important than additive effects in the inheritance of these traits. The contribution of lines was larger than that of testers and lines x testers interaction in most traits at both environments indicating the importance of selection of lines for hybridization, and selection should be delayed to later generations.