A bacterial strain designated YY287(T), isolated from food waste compost, was investigated by polyphasic taxonomic approach. The cells were rod-shaped, Gram-negative, non-pigmented, non-spore-forming and non-fermentative. Phylogenetic analyses using the 16S rRNA gene sequence showed that the strain formed a monophyletic branch towards the periphery of the evolutionary radiation occupied by the genus Comamonas; its closest neighbours were the type strains Comamonas testosteroni DSM 50244(T) (96.5%), Comamonas terrigena DSM 7099(T) (95.4%), Comamonas odontotermitis Dant 3-8(T) (95.2%) and Comamonas koreensis KCTC 12005(T) (94.6%). Strain YY287(T) was clearly distinguished from all of these strains using phylogenetic analysis, DNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics. The major fatty acids were 16:0 (33%), 18:1omega7c (13%) and summed feature 3 (16:1omega7c and/or 15:0 iso 2-OH; 41%). The DNA G+C content of the genomic DNA was 62.8 mol%. It is evident from the genotypic and phenotypic data that strain YY287(T) represents a novel species in the genus Comamonas, for which the name Comamonas composti sp. nov. is proposed. The type strain is YY287(T) (=BCRC 17659(T)=LMG 24008(T)).