Bitter vetch (Vicia ervilia (L.) Willd.), a grain legume crop well adapted in marginal soils, has mainly been used for animal feed. Nowadays, bitter vetch seeds in feed formulations are replaced by other protein sources such as soybean meal. However, in the context of sustainable economic development, it may be beneficial to enhance the cultivation of bitter vetch landraces in marginal areas. Fifty-six bitter vetch accessions of different provenance were preliminarily characterised by microsatellite DNA analysis to discriminate landraces suitable for specific and restricted environments. Twenty-two landraces of two genetically different groups were then selected for further characterisation by agro-morphological analyses. Being late-flowering with a seed yield of up to 3–4 t ha^–1 in experimental field conditions, with neither chemical nor water input, these plants will be valuable material for long-term study to develop new cultivars adapted for seed production under organic agricultural systems in Southern Europe. The seeds of these 22 landraces were also evaluated, with positive results, as partial replacement of soybean in rabbit diets.