A Gram-negative, aerobic, motile and rod-shaped bacterium, designated strain T7-07(T), was isolated from compost in Daejeon, Korea. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain T7-07(T) had 99.0% gene sequence similarity with Arenimonas malthae KACC 14618(T) and 94.7-95.9 % with other recognized species of the genus Arenimonas. Cells formed creamy white to yellowish colonies on R2A agar and contained Q-8 as the predominant ubiquinone, C-15:0 iso, C-16:0 iso, C-17:1 iso omega 9c and C-11:0 iso 3-OH as the major fatty acids, and diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmethylethanolamine and an unknown aminolipid as the major polar lipids. The DNA G + C content of strain T7-07(T) was 68.3 molok. DNA-DNA reassociation experiments between T7-07(T) and Arenimonas malt hae KACC 14618(T) resulted in a mean relatedness value of 22.2%. Combined genotypic and phenotypic data supported the conclusion that the strain T7-07(T) represents a novel species, for which the name Arenimonas daejeonensis sp. nov. is proposed. The type strain is T7-07(T) (=KCTC 12667(T)=DSM 18060(T)).