A novel strain, designated Gsoil 664(T), isolated from the soil of a ginseng field in South Korea, was characterized by a polyphasic approach to clarify its taxonomic position. The isolate was Gram-negative, strictly aerobic, heterotrophic, non-motile, non-spore-forming and possessed rod-shaped cells. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolate formed a cluster with several uncultured bacterial clones and with the established genera Terrimonas, Niastella and Chitinophaga in the phylum Bacteroidetes. However, the isolate was clearly separated from these genera: the gene sequence similarities with respect to the type strains of recognized species from closely related genera ranged from 86.7 to 90.7 %. The G+C content of the genomic DNA was 40.4 mol%. The predominant isoprenoid quinone was MK-7. The major fatty acids were iso-C(15 : 0), iso-C(17 : 0) 3-OH, iso-C(15 : 1) and C(16 : 1) omega 5c. The results of physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain Gsoil 664(T) from recognized species of related genera. On the basis of the polyphasic evidence, Gsoil 664(T) represents a novel genus and species, for which the name Segetibacter koreensis gen. nov., sp. nov. is proposed. The type strain of S. koreensis is Gsoil 664(T) (=KCTC 12655(T)=DSM 18137(T)).