An experimental work was undertaken to evaluate some legumes cultivated in Spain (lupins, kidney bean, peas and faba beans) and to obtain protein concentrates with reduced contents in antinutritional factors. The estimation of moisture, ash, lipid content, protein and fiber, using standard methodology, reflected marked differences among the studied species as well as in the content of antinutritional factors (lectins, trypsin inhibitors, phytates, tannins and saponins). The levels of antinutritional factors of protein nature in the concentrates were decreased by the treatment. These legumes, currently cultivated in the EC could represent an important source of nutrients of vegetable origin with low levels of the assayed antinutritional factors, particularly for faba beans and peas. The preparation of protein concentrates constitutes an alternative approach for using these seeds for nutritional purposes.