Six Sigma methodology has been established as a process-oriented approach with strong emphasis on results and effectiveness, aiming to improve the quality of products, services, and processes. In our country, in line with global developments, industrial and service organizations have rapidly become aware of the high potential of this methodology through information exchange with international organizations and industrial centers, and have been encouraged to implement it. The main objective of this methodology is the implementation of a measurement-based strategy focused on process improvement and variability reduction. Sarcheshmeh Copper Complex, as one of the major and foundational industries of the country, has defined numerous Six Sigma projects to improve production processes, reduce waste, and increase productivity, achieving extensive benefits such as improvement of production processes, reduction of losses and scrap, and significant financial savings. Since one of the main concerns of managers at the Sarcheshmeh Copper Complex is reducing the amount of cold material produced in the smelting plant and consequently preventing the waste of a considerable portion of incurred costs a Six Sigma project was therefore considered to address this issue. In this research, simulation tools were also utilized to develop an integrated model for reducing cold material in the smelting process. For this purpose, a discrete-event system simulation approach was employed. The design and implementation of the simulation model were carried out using Arena software and Visual Basic.