Drought is a serious problem in rainfed areas due to rapid change in climatic conditions. Among prevailing a biotic stresses, it is the most significant and severe factor inhibiting plant growth and production through impairing normal growth, disturbance of water relations, reduction of water use efficiency and yield performance. The objective of this study was to evaluate morphological, physiological and yield performance of sorghum introgression lines under post flowering stress. The field experiment was conducted on seven stay-green QTLs introgression lines (marker assisted backcrossing derivatives), two stay-green donor parents and three recurrent parents obtained from Melkassa Agricultural Research Center. The experimental materials were tested in split plot design under well watered (WW) and drought stress (DS) growing conditions at Melka Werer field site during the post-rainy cropping season of 2014. The combined ANOVA revealed that effect due to moisture regimes (MR) was highly significant (P < 0.05) for all traits. Differences among the genotypes were also highly significant (P < 0.05) for all traits considered. Post-flowering drought stress reduced morphological, physiological and yield related traits relative to the well watered condition.