Lean Six Sigma implementation has been expanded into diverse industry sectors for a variety of objectives. Recently, the application of Lean Six Sigma into improving environmental performance is noted by practitioners, even though there is very few or no academic literature discussing the implementation. This generates the new research opportunities for academia. Thereby, the research is born to fill out the gap between academic study and industrial practice, and to encourage the execution through pragmatic experience and theoretical analysis. The overall aim of this study is to explore the value of Lean Six Sigma in environmental sustainability. A two-step research is designed to demonstrate the process of exploiting Lean Six Sigma application at environmental perspective and the research results. In general, the research process is simplified as "discover the value" and "add the value". Although this thesis focuses on the value of Lean Six Sigma implementation into environmental sustainability, it emphasizes the application in industrial field and broadens the perceptive of Lean Six Sigma application, and introduces further research opportunities in this research area.