Avenin is polymorphic, specific alcohol-soluble spare protein which is successfully applied to the analysis of a genetic variety of oats. Components of avenin are inherited by groups and controlled by three independent loci of Avn A, Avn B and Avn C. The research objective was studying of a genetic variety of the grades of summer oats recommended for using in Siberia on electroforetic ranges of avenin. On the basis of the received electroforetic ranges of spare proteins the allelic structure of the avenin-coding loci of grades of oats sowing were analyzed. Two of the studied grades were hetero-geneous and consisted of 2 biotypes. On a locus of Avn A alleles for four studied grades were not iden-tified. Perhaps, these allelic options can act as markers of adaptability of forms of oats to the Sibe-rian conditions. On Avn B locus in ranges of the studied grades 5 various alleles were revealed, on-ly one of them was missing in the available cata-logues. Two grades were heterogeneous on this locus. Interhigh-quality differences on a locus of Avn C were minimal: at 6 grades the C2 option was identified, at separate grades alleles of C1, C5 and C6 were revealed. All analyzed grades differed from each other on the component structure of avenin that was connected with the high level of polymorphism of the prolamin controlled by Avn B locus. The results can be used for variety identifica- tion, determination of the extent of their relation- ship, and also in control of varietal purity batches of seeds.