The common oat (Avena sativa L.) is an excellent source of nutritional compounds. The objectives of this study were: (1) to identify oat accessions cultivated in Russia with high nutritive values of grain components, including iron (Fe), zinc (Zn), manganese (Mn), protein, oil and fatty acids, and (2) to determine how the measured components are interrelated. Fifty oat accessions from the Russian germplasm collection held at the Vavilov Institute of Plant Genetic Resources were characterized. Considerable genetic variation appeared to exist in almost all nutritional contents among genotypes grown in the same environment. Genotypic variations for seed Fe and Zn were moderate (1.9-2.7-fold), while those for Mn were relatively high (10.5-fold). A 1.8-fold variation between the lowest (10.9%) and highest (19.3%) protein content in the oat grain was found. High variation in oil content (2.7-8.1%) was found among the 50 cultivated oat accessions. Major fatty acids in oat oil were linoleic (C18:2) and oleic (C18:1) acids with higher C18:2 than C18:1 in all accessions. Oil, oleic acid, protein and Zn content show a positive correlation. The identified oat cultivars with high nutritive values would be promising for breeding programs and for providing important nutrient sources for human consumption.