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Soil amendments with plant materials from <i>Medicago</i> species are widely acknowledged for a suppressive effect on plant-parasitic nematodes but their impact on beneficial components of soil nematofauna is still unknown. A study on potted tomato was carried out to investigate the short-time effects on the overall nematofauna of dry biomasses from six different <i>Medicago</i> species, i.e., <i>M. sativa</i>, <i>M. heyniana</i>, <i>M. hybrida</i>, <i>M. lupulina</i>, <i>M. murex</i> and <i>M. truncatula</i>, incorporated to natural soil at 10, 20, or 40 g kg⁻¹ soil rates. All amendments resulted in a significant decrease of the total nematofauna biomass, whereas total abundance was significantly reduced only by <i>M. heyniana</i>, <i>M. hybrida</i>, and <i>M. lupulina</i> biomasses. Almost all the <i>Medicago</i> amendments significantly reduced the relative abundance of plant-parasites and root fungal feeders. All amendments significantly increased the abundance of bacterivores, whereas fungivores significantly increased only in soil amended with <i>M. heyniana</i>, <i>M. lupulina</i> and <i>M. sativa</i> plant materials. <i>Mesorhabditis</i> and <i>Rhabditis</i> were the most abundant genera of bacterivores, whereas <i>Aphelenchoides</i> and <i>Aphelenchus</i> prevailed among the fungivores. Predators were poorly influenced by all the tested <i>Medicago</i> biomasses, whereas the abundance of omnivores was negatively affected by <i>M. heyniana</i> and <i>M. lupulina</i>. Values of the Maturity Index and Sum Maturity Index were reduced by treatments with <i>M. heyniana</i>, <i>M. hybrida</i>, <i>M. lupulina</i> and <i>M. sativa</i> plant materials, whereas most of the tested amendments decreased values of the Channel Index while increasing those of the Enrichment Index. Enrichment and bacterivore footprints raised following soil addition with <i>Medicago</i> biomasses, whereas composite and fungivore footprints were significantly reduced. According to their overall positive effects on soil nematofauna, amendments with <i>Medicago</i> plant materials or their formulated derivatives could represent an additional tool for a sustainable management of plant-parasitic nematodes.