The specimens collected from American mink (Neovison vison) and European polecat (Mustela putorius) in Lithuania were morphologically identified as Isthmiophora melis (Schrank, 1788) Lühe, 1909 and were molecularly characterized through sequencing of partial 18S rDNA, 28S rDNA, ITS1- 5.8S-ITS2 region, and ND1. Relations of I. melis to other species of the genus Isthmiophora Lühe 1909 were discussed. According to ITS1 and ND1 sequences the closest species to I. melis is Isthmiophora hortensis (Asada, 1926).