Business organizations may be able to improve their Sustainability Performance (SP) by adopting Total Quality Management (TQM) concepts combined with Industry 4.0 (I4.0) technologies. This research has developed a model to investigate the influence of TQM and I4.0 on SP. It also analyzes the mediating role of TQM in the relationship between I4.0 and SP. A survey was conducted among 240 respondents employed in ready-made garment (RMG) industries in Bangladesh. A Structural Equation Modelling (SEM) technique was used to analyze the collected data. Research findings show that both TQM and I4.0 technologies have a significant impact on the sustainable growth of the Bangladeshi RMG sector. Moreover, it is observed that TQM mediates the relationship between I4.0 and SP. The findings show that TQM helps to explain the relationship between I4.0 and sustainable performance. This study will provide a guideline for industrial executives on securing sustainability through the adoption of TQM concepts and I4.0 technologies. We are not aware of any additional studies that look at the possible link between TQM, I4.0, and SP, as well as the mediating role of TQM between I4.0 and SP.