A Gram-negative, non-spore-forming, yellow-pigmented bacterium, strain N4T, was isolated from a nickel-complexed cyanide-degrading bioreactor and subjected to a polyphasic taxonomic study. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain N4T is affiliated to the genus Chryseobacterium of the family Flavobacteriaceae. The levels of 16S rRNA gene sequence similarity between strain N4T and the type strains of all known Chryseobacterium species were 93.2–95.8 %, suggesting that strain N4T represents a novel species within the genus Chryseobacterium. The strain contained iso-C15 : 0 and summed feature 4 as the major fatty acids and menaquinone MK-6 as the predominant respiratory quinone. The G+C content of the genomic DNA was 38.2 mol%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain N4T represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium caeni sp. nov. is proposed. The type strain is N4T (=KCTC 12506T=CCBAU 10201T=DSM 17710T).