The taxonomic positions of five Gram-negative, non-spore-forming and non-motile bacterial strains isolated from the rhizosphere of sand dune plants were examined using a polyphasic approach. The analysis of the 16S rRNA gene sequence indicated that all of the isolates fell into four distinct phylogenetic clusters belonging to the genus Chryseobacterium of the family Flavobacteriaceae. The 16S rRNA gene sequence similarities of isolates to mostly related type strains of Chryseobacterium ranged from 97.5% to 98.5%. All strains contained MK-6 as the predominant menaquinone, and iso-C(15:0), iso-C(17:0) 3-OH and a summed feature of iso-C(15:0) 2-OH and/or C(16:1) omega7c as the dominant fatty acids. Combined phenotypic, genotypic and chemotaxonomic data supported that they represented four novel species in the genus Chryseobacterium, for which the names Chryseobacterium hagamense sp. nov. (type strain RHA2-9(T)=KCTC 22545(T)=NBRC 105253(T)), Chryseobacterium elymi sp. nov. (type strain RHA3-1(T)=KCTC 22547(T)=NBRC 105251(T)), Chryseobacterium lathyri sp. nov. (type strain RBA2-6(T)=KCTC 22544(T)=NBRC 105250(T)), and Chryseobacterium rhizosphaerae sp. nov. (type strain RSB3-1(T)=KCTC 22548(T)=NBRC 105248(T)) are proposed.