The stone marten (Martes foina) is one of the most common species of marten in Europe. Due to increased urbanization and forest degradation, it is now often found in urban habitats, which increased the possibility of parasites transmission between wildlife-domestic animals and humans. Our preliminary study of this mustelid in Portugal, aimed to assess prevalence of helminths. Six helminth parasites were found (Crenosoma vulpis, Angiostrongylus sp., Toxocara sp., Toxascaris leonina, Ancylostomatidae and Strongyloides sp.). To our knowledge, this is the first report of Toxascaris leonina in this host species.