The application of constructed wetlands (CWs) has significantly expanded to treatment of various industrial
effluents, but knowledge in this field is still insufficiently summarized. This review is accordingly
necessary to better understand this state-of-the-art technology for further design development and new
ideas. Full-scale cases of CWs for treating various industrial effluents are summarized, and challenges
including high organic loading, salinity, extreme pH, and low biodegradability and color are evaluated.
Even horizontal flow CWs are widely used because of their passive operation, tolerance to high organic
loading, and decolorization capacity, free water surface flow CWs are effective for treating oil field/re-
finery and milking parlor/cheese making wastewater for settlement of total suspended solids, oil, and
grease. Proper pretreatment, inflow dilutions through re-circulated effluent, pH adjustment,
plant selection and intensifications in the wetland bed, such as aeration and bioaugmentation, are
recommended according to the specific characteristics of industrial effluents