SDS-PAGE technique was used for the study of seed protein polymorphism among three genotypes of Abrus precatorius with different seed coat colour. A total of 44 polypeptide bands were recorded. Out of these 26 were common among all three genotypes and 18 (40.90%) were polymorphic. The data analysis using UPGMA clustering revealed that genotypes with black and white seed coat colour were closer as compared to genotype with red seed coat colour. Each of three genotypes of A. precatorius had some polypeptide bands which were peculiar to them only. This enabled distinguishing all three genotypes on the basis of specific polypeptide fragments using SDS-PAGE analysis.