The aim of this study was to assess the variations amongeset a half diallel cross using eight varieties and or / lines for drought characters, estimating combining ability and genetic components. For this objective, the investigation was carried out at the Experimental Farm of Gemmeiza Agricultural Research Station during the two seasons 2007/2008 and 2008/2009, Eight diverse barley varieties and/or lines (Hordeum vulgare, L.) and 28 F1's were planted in two experiments. The first experiment was normally irrigated three times at tillering, elongation and heading stages. The second one irrigated only once at tillering stage. The main results can be summarized as follow ; the water stress treatment decreased the means of relative water content (RWC), total soluble solids (TSS), flag leaf angle (FLa), number of spikes/plant (NS/P), number of kernels/spike (NK/S), 100–kernel weight (100-KW) and grain yield/plant (GY/P) for parents and their hybrids. Irrigation mean squares were significant for all traits , Line 9 was the best combiner under both conditions and Giza 124, Line 5 and Giza 126 under stress and the combined analysis for grain yield, where the best hybrids were Giza 126 x Giza 123 and Giza 126 x Line 10 for earliness and Line 5 x Line 6, Line 6 x Line 4,Giza 126 x Giza 123 and Line 10 x Line 4 for grain yield at both conditions. The heritability estimates ranged from 0.022 for TSS under stress condition to 0.50 for NS/P under normal condition