Drought stress is the most important factor restricting crop production in the majority of agricultural fields in the world. Durum wheat is generally grown in arid and semi-arid areas and drought often causes serious problems in its production. Fourteen durum wheat genotypes were evaluated under semi-arid Mediterranean climatic conditions in two non-stressed and water-stressed conditions. Data on fourteen agronomic traits are presented to assess the phenotypic diversity and to investigate the relationships between grain yield and other important yield components in durum wheat. The coefficient of variation (CV) for all the genotypes ranged from 0.71% to 17.62% in non-stressed environment and ranged from 1.38% to 23.70% in water-stressed environment. Clustering based on durum wheat genotypes separated the measured traits into three main groups under non-stressed environment. Peduncle length, agronomic score and plant height were the most related traits with grain yield. Such clustering in water-stressed environment indicated that growth vigor, thousand kernel weight, test weight or hectoliter and agronomic score were the most associated traits with grain yield. Cluster analysis assigned the durum wheat genotypes to at least two major groups in non-stressed conditions and three major groups in water-stressed conditions. Therefore, it seems that for improving grain yield performance in non-stressed conditions, genotypes G1, G3, G4, G6, G8 and G13 and in water-stressed conditions, genotypes G3, G8, G10 and G14 are good candidates. Finally, for improving grain yield performance in both humidity conditions, genotypes G3 and G8 can be used.