Abstract: The invention is a method for the treatment and decolorization of waste water incident to the manufacturing of cosmetic products that contains dyestuffs, fatty organic chemicals and other organic chemicals. The method requires a strong base which is added to the waste water at a suitably high temperature to cause flocculation of fatty substances. Then an strong colorless oxidizer is added to reduce the hydrophilic character of the remaining organic chemicals and cause partial decolorization. The resulting waste water is in a state that can then be decolorized with powdered activated carbon. Finally, the powdered activated carbon is separated from the waste water. The decolorized waste water is discharged in compliance with acceptable water quality standards for plant effluents.