Detergent removal from wastewater treatment is important for environmental protection. Biosorption of detergent onto the activated sludge enables aerobic treatment of the wastewater. This paper presents a further improvement of the method by a massive destruction of the detergent through a prolonged mixing of the detergent with the activated sludge prior to the aeration process. This is possible as detergent is a cleaning agent and can breakdown the activated sludge through intimate contact in the mixing process. Thickening of the activated sludge and culturing activated sludge with high biosorption capacity ensures the intimate contact for the detergent destruction action. Breaking down of the activated sludge provides a high loading condition which favors the growth of microorganism with strong biosorption capacity. The method was successfully implemented in the detergent packing plant.