Fifteen species belonging to 3 genera (Onobrychis, Hedysarum and Sartoria), collected from different geographical regions of Turkey were studied for the polypeptide patterns of their seed storage proteins. The variability of seed storage proteins was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). As many as 72 bands were scored and a dendrogram was constructed using UPGMA (unweighted pair group method with arithmetic mean). The dendrogram of the electrophoretic protein profiles of seeds showed 2 main clusters. While the first cluster with further subclusters included Onobrychis species, the second cluster included Sartoria and Hedysarum species present in 2 separate subclusters. The results showed that Sartoria and Hedysarum are closer to each other than they are to Onobrychis. It is also suggested that Sartoria hedysaroides should be included in the genus Hedysarum. Additionally, it is concluded that seed storage protein profiles could be useful markers in studies of genetic diversity, genetic relationships, and classification of adapted cultivars. © TÜBITAK.