In Ethiopia, the low productivity of garlic is largely due to a shortage of high yielding and stable varieties. To address this issue, thirteen garlic genotypes were evaluated for yield stability and performance across six different environments in central and southeast Ethiopia. The genotypes were analysed using Additive Main effects and Multiplicative Interaction (AMMI) and genotype-by-environment interaction (G × E) methods. Results showed that the genotypes differed significantly for bulb yield performance and morphological traits, with G-020/03 and G-054/03 producing the highest bulb yield with 25.39% and 18.39% yield advantages over the check variety, Kuriftu, respectively. Furthermore, G-020/03 demonstrated better yield stability across most environments, while G-054/03 exhibited specific adaptability. GGE biplot analysis confirmed that these two genotypes were among the three winning genotypes in terms of yield performance and relative stability. Therefore, G-020/03 and G-054/03 have been selected as candidate varieties for release, potentially improving garlic productivity in Ethiopia.