The aim of this investigation was to study the performance and phenotypic stability of some wheat genotypes for grain yield under different imgated environments Eight parental cuttivars and loi lines and their 28 F1 hybrids. representing a wide range of variability in drought tolerance, were grown in a randomized complete block design with three replications in both Zarzora and Shibin El-Kom locations. Four adjacent experiments were conducted in eaci) location, the first, second, third and fourth experiments were irrigated one, two, three and four times after planting irrigation, respectively. Phenotypic stability for grain yield was computed according to Ebertiart and Russell (1966). This analysis was done on eight different environments (two locations and four irrigation treatments in each location). The five crosses. (2 x 6). (3 x 6), (4 x 5). (4 x 7) and (4 x 8). were more stable than the others under the environments ڑtudied. Some of the unstable genotypes seemed to have high grain yields above the grand mean. These genotypes. however. could be overlooked, as their high yield potential was limited to particular environments. Other stable genotypes had mean yields below the grand mean. These genotypes might be fruitful under stress environments Keywords: Wheat, grain yield. irrigation, stress environments. phenotypic stability.