The biochemical composition (the content of protein and lipids, the content of essential amino acids in the protein complex, the fatty acid composition of lipids) of seeds of eighteen soyabean varieties cultivated in different soil-climatic zones under various weather conditions was examined. Changes in the biochemical parameters were primarily associated with the genotype of the variety. The effect of weather, soil and climatic conditions was less marked. With an increase of the protein content the concentration of lysine and methionine in proteins tended to decrease. As long as the oil content in seeds grew, the concentration of oleic acid increased and that of linoleic and linolenic acids decreased.