A novel strain K-4-16(T) was isolated from forest soil of Namsan Mountain, Seoul, South Korea, and was taxonomically characterized by a polyphasic approach. Strain K-4-16(T) was observed to be a Gram-staining negative, grayish white-coloured, motile with peritrichous flagella, and rod shaped bacterium. It was able to grow at 15-45 degrees C, at pH 4.5-10.5, and at 0-4% (w/v) NaCl concentration. Based on the 16S rRNA gene sequence analysis, strain K-4-16(T) belongs to the genus Acidovorax and is closely related to Acidovorax anthurii CFBP 3232(T) (98.3% sequence identity), Acidovorax konjaci K2(T) (97.9% sequence identity), Acidovorax valerianellae CFBP 4730(T) (97.8% sequence identity), and Acidovorax caeni R-24608(T) (97.8% sequence identity). The only respiratory quinone was ubiquinone-8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The predominant fatty acids of strain K-4-16(T) were summed feature 3 (C(16:1)7c and/or C(16:1)6c), C-16:0, and summed feature 8 (C(18:1)7c and/or C(18:1)6c). The genomic DNA G+C content of this novel strain was 64.7mol%. The DNA-DNA relatedness between strain K-4-16(T) and its reference strains were below the threshold value of 70%. The morphological, physiological, chemotaxonomic, and phylogenetic analyses clearly distinguished this strain from its close phylogenetic neighbors. Thus, strain K-4-16(T) represents a novel species of the genus Acidovorax, for which the name Acidovorax monticola sp. nov. is proposed. The type strain is K-4-16(T) (=KEMB 9005-570(T)=KACC 19171(T)=NBRC 113141(T)).