This study was conducted to determine genotype environment interactions and the stability status of twelve Hungarian vetch (Vicia pannonica Crantz.) genotypes in terms of dry-matter yield and seed yield under the ecological conditions of the Southeastern Anatolia Region of Turkey. The experiments were performed in five locations in the region during the 2008-2009 and 2009-2010 growing seasons. The experiments were performed according to a complete randomized block design with three replications. Genotype environment interactions were found to be highly significant (P < 0.01) for dry-matter yield and seed yield, indicating that the Hungarian vetch genotypes' dry-matter yield and seed yield were significantly affected by the year and condition of the location. The stability of the genotypes was estimated using the mean yield of genotypes (x(i)), regression coefficient (bi), regression deviation mean square (S(2)d(i)), determination coefficient (R-2), and regression line intercept (a). Stability analysis indicated that although the most stable genotype was the Ege Beyazi-79 cultivar in terms of dry-matter yield, the Oguz-2002 cultivar was the most stable in terms of seed yield.