A non-motile, coccobacilli-shaped, pale-pink-pigmented bacterium, designated strain CW67(T), was isolated from a water-cooling system in Gwangyang, Republic of Korea. Cells were found to be Gram-negative, catalase-positive and oxidase-positive, the major fatty acids were C(18 : 1)omega7c (43.6 %) and C(16 : 0) (15.8 %), the predominant respiratory lipoquinone was Q-10 and the DNA G+C content was 69.5 mol%. A phylogenetic tree based on 16S rRNA gene sequence comparisons showed that strain CW67(T) forms an evolutionary lineage within the radiation of the genus Roseomonas and that its closest relative is Roseomonas gilardii subsp. rosea MDA5605(T) (94.7 % sequence similarity). Evidence from this polyphasic study showed that strain CW67(T) could not be assigned to any recognized species. It therefore represents a novel species, for which the name Roseomonas frigidaquae sp. nov. is proposed, with CW67(T) (=KCTC 22211(T) =JCM 15073(T)) as the type strain.