Selecting wastewater treatment technology is not an easy matter. In this study, TOPSIS and AHP methods are used to support decision-making in choosing a wastewater treatment alternative for Poong In Vina factory. A total of 9 criteria belonging to 3 groups of economic, social - technical and environmental issues were used to select an alternative. The results of TOPSIS and AHP analysis showed that aerobic biotechnology integrated with membrane bioreactor technology is the optimal solution. The outcomes of this study will help the company in choosing the best option among these technologies. Furthermore, it will provide an insight for relevant stakeholders such as engineers, manufacturers and other ogranizations for making decisions.