Seeds of amaranth plant grown from He-Ne laser light and magnetic field stimulated seeds or from seeds treated with both pre-sowing stimulating methods were analysed for the chemical composition and their nutritive values. Pre-sowing stimulation resulted in increase of dry matter, crude protein, crude fibre and crude ash. Decrease in crude oil and in the level of carbohydrates was generally observed. Use of different methods of presowing stimulation resulted in different response of the seeds in the amino acid composition. Generally, increase in the level of Leu, Lys, Val and Phe + Tyr was observed. At the same time a decrease in the levels of Arg, Glu and Ala was observed. Levels of Cys, Thr, Ile, His and Pro were not affected. The most nutrition-effective was protein from magnetic field stimulated seeds. The energetic values of the flours decreased. The electromagnetic stimulating methods are promising and non-invasive tools in the improvement of the composition and amino acid content of amaranth seeds. Of importance is the observed gain in the level of crude fibre and crude ash, as well as increase in the level of Leu which is normally the limiting amino acid in amaranth.