Soya bean (Glycine max (L.) Merr.) is a legume valued for, among other things, the high nutritional value of its seeds, which contain around 40% protein with an excellent amino acid composition and a significant fat content. The study aimed to evaluate the protein, fat, fibre and amino acids content of the seeds of two soya bean varieties sown at different row spacings under organic and conventional growing conditions. The study showed that the conventional method of production has a more favourable effect on the soya bean’s protein content and the most amino acids, primarily essential amino acids. In organic cultivation, soya bean seeds were characterised by a higher content of fat and sulphur amino acids (methionine and cysteine). The research carried out indicates that the seeds of the Aldana variety, compared to the Merlin variety, have greater nutritional importance to humans due to a higher content of protein and almost all amino acids, including essential amino acids. Only a higher content of seed fat and tryptophan was evidenced in the Merlin variety. Row spacing did not significantly differentiate the assessed soya bean seed quality parameters. Only the amount of methionine was significantly higher when soya beans were grown at a narrower row spacing (22.5 cm).