This research was carried out to determine the macronutrient content in dry grass of barley, which is mixed with common vetch and hairy vetch in different proportions. Field trials were conducted at Siirt University (Turkey) for two years in the winter season of 2017-18 and 2018-19. Common vetch (YF), hairy vetch (TF) and barley (A) plants were grown sole, and each vetch species was grown mixed with barley in four different mixing ratios (80:20, 60:40, 40:60, 20:80). Phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) ratios were determine in the harvested grass. As the average of two years; the highest Ca content (1.08%) was obtained by the "20 YF + 80A" mixture, whereas the highest K content (4.50%) was obtained from the "sole common vetch", the highest Mg content (0.21%) was obtained from the "80YF + 20A" mixture and the highest P content (0.34%) was obtained from the "20TF + 80A" mixture. It is found that the grass of these legumes in sole and their mixture with barley are at a sufficient level in terms of Ca and K; but in terms of Mg and P, they were found below the required limit value for feed rations. It was concluded that the Ca / P ratio of hay obtained from both sole and mixed cultivation poses a risk for animal health. According to these results; it is proposed to add Mg and P-containing substances to the studied grasses. Or mixing them with Mg and P-rich feeds might be a good option.