A novel strain (designated sjH1T), characterized as aerobic, Gram-stain-negative, oxidase-positive, catalase-negative, motile and rod-shaped, was isolated from mine wastewater. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain sjH1T belonged to the genus Rhodanobacter. Strain sjH1T was closely related to Rhodanobacter thiooxydans LCS2T (98.0% 16S rRNA gene sequence similarity), Rhodanobacter denitrificans 2APBS1T (97.7%), Rhodanobacter soli DCY45T (97.2%) and Rhodanobacter caeni MJ01T (97.0%). The DNA G+C content of strain sjH1T was 69.2 mol%. DNA-DNA relatedness ( < 60%) indicated that strain sjH1T represents a distinct species that is separate from R. thiooxydans, R. denitrificans, R. soli and R. caeni. The major ubiquinone was Q-8, and major fatty acids were summed feature 9 (iso-C17 : 1ω9c and/or C16 : 0 10-methyl), iso-C15 : 0, iso-C17 : 0, iso-C16 : 0 and anteiso-C15 : 0. Based on data from this polyphasic study, it is proposed that sjH1T ( = KCTC 42660T = JCM 30774T) is the type strain of a novel species, Rhodanobacter aciditrophus sp. nov.