Nowadays, considering the limitedness of resource and environmental pollution, development and utilization of materials for the future must be considered the harmony with natural environment, and they do not destroy the ecosystem at the same time. The main target of this study was the development and assessment of the eco-concrete using recycled-aggregate for improving water quality. At the same time, influence of mix factors and mixture proportion of aggregate were investigated to obtain the best condition of eco-concrete for strength and water permeability, and quantity characteristics of attached biomass for each eco-concrete were also investigated for improving water quality. The results of an experiment study on water purification by contact oxidation water treatment basin using eco-concrete are reported. The average removal efficiency of SS, COD, TN, TP were 91%, 47%, 50%, 63% respectively at the contact oxidation water treatment basins.