A soil column was percolated with Triton X-100 (octylphenol polyethoxylates; OPEOn) under aerobic conditions for 300 days and OPEOn-degrading bacteria were isolated and characterized phylogenetically. Populations of total culturable bacteria and OPEOn (1000 mg L −1 )-resistant bacteria increased 10 times and 46 times, respectively, during the percolation. 16S rRNA gene sequencing of 128 OPEOn-resistant isolates revealed an increase in the population level of Alphaproteobacteria and decreases in levels of Betaproteobacteria and Actinobacteria with the exposure to the compound. Four OPEOn-degrading strains were isolated and characterized as being related to Bradyrhizobium liaoningense (3 strains) and Afipia sp. (1 strain).