The purpose of the study was to determine the stability and yield performances of 20 bread wheat cultivars grown in nine different environments. The trials were arranged in a Randomized Complete Block Design with four replications. Additive main effects and multiplicative interactions analysis (AMMI-biplot) indicated that the yield performances of bread wheat cultivars were highly affected by the major environmental factors. The first two principal component axes (PCA 1 and PCA 2) were significant and they explained 60.9 % of the total genotype x environment interaction. A biplot generated using genotypic and environmental scores of the first two AMMI components demonstrated that cultivars with larger PCA 1 and lower PCA 2 scores were high yielding and stable cultivars and cultivars with lower PCA 1 and larger PCA 2 scores were low yielding and unstable cultivars in tested locations. It could be concluded that the Basribey 95 had the highest yield performance and also the stable genotype in the test locations. Đzmir 85 and Ziyabey 98 were poorly stable although they showed high yield performances in some of test environments. Momtchill had the lowest yield performance in all test locations. It was detected that Menemen location could be the most representative among the tested locations to determine the stability of bread wheat cultivars to recommend the farmers in the Western Coastal Zones in the Aegean Region under Mediterranean climatical conditions of Turkey.