As the level of automation is increasing among industries, the increasing amount of waste has become one of the main barriers to having a sustainable environment. That’s why the sustainable manufacturing concept came to bring economic benefits while focusing on minimizing negative environmental impacts. The purpose of this study is to show the importance of waste reduction in manufacturing processes to achieve a higher level of sustainability. This work uses the production processes of a textile garment factory located in Bangladesh as a case study to examine how waste reduction can be achieved. First, the major steps of the production process are mapped and visualized to identify improvement opportunities by using the Business Process Modeling Methodology and discrete event simulation. Second, after the production process is improved, an experimental test was conducted to see how much waste reduction can be achieved by the proposed solution. The research found that the in-sewing wastage in the factory was too much and used compressed air as a suggested solution to minimize this problem. The final result of the test showed that the in-sewing fabric wastage percentage had been reduced almost by 75 %, indicating the possible benefits of this solution regarding sustainability, if applied on a larger scale within the factory.