Abstract: A photo-chemical remediation of Cu-CMP waste streams basically includes the following acts: adding photo-catalyst particles into waste streams containing copper ions and organic pollutants and exposing the waste streams to UV light or sunlight to make copper ions become deposited on surfaces of the photo-catalyst particles. Whereby, the copper ions are removed from the waste streams. Meanwhile, organic and inorganic pollutants are decomposed by the photolysis capability of the photo-catalyst to make the waste streams dischargable within environmental standards to the environment.