THIS STUDYwas conducted to evaluate twenty covered barley (Hordeum vulgare L.) genotypes for high yield potential and stable performance under two irrigation treatments (irrigated and water stressed).Totaldry matter accumulation (TDM), leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), relative growth rate (RGR), relative water content (RWC), relative chlorophyll content (RCC), grain yield and biological yield were evaluated during two successive seasons 2009/10 and 2010/11 at Sakha Res. Station. All parameters studied had a negative significant effects as a result of water stressin both growing seasons, except for relative chlorophyll content, which increased under stress conditions compared with the normal irrigation. Results showed that L4 and L8 genotypes had the heaviest biological yieldandgrain yield, where they had the highest values of TDM, LAI and CGR especially under stress condition, as well as possessed good values of NAR, RGR and RCC, revealing that these genotypes were more tolerant to water stress and more desirable genotypes for both stress and non-stress conditions.