Abstract: This research was undertaken to evaluate the performance of parental lines and their crosses under different environments for yielding ability and some traits and determine the most stable lines and hybrids. Testing newly developed genotypes under several environments is important for evaluating stability of performance and range of adaptation. Twenty five F1 and their 10 parents of sorghum were evaluated at two locations (Assiut and Qena governorates) under early and late sowing dates in both 2007 and 2008 summer seasons. Year effects were significant for the studied traits. Location and date effects had the largest impact on the studied traits. The interaction effects of genotype with each of locations and dates were highly significant for all studied traits whereas genotype x year interaction effect was highly significant for days to blooming, plant height and grain yield. Genotype x year x date interaction effect was highly significant for plant height, 1000-grain weight and grain yield. However, genotype x year x location x date interaction effect was highly significant only for plant height and grain yield. Most of hybrids were significantly earlier, taller, heavier grain weight and higher grain yield compared to their parents and checks. Stability analysis for grain yield demonstrated that most of F1 hybrids had higher yields than their parents, but the parents were relatively more stable. Four genotypes (three crosses; (A-73 x R-272), (A-604 x R-92010) and (A-613 x R-210) and one parent (R-273)) were the best stable genotypes. These genotypes gave higher yields compared to the average overall genotypes (hybrids and parents, respectively). These genotypes are considered as promising cultivars and it may be suitable for growing in a wide range of environments.