Total quality management (TQM) is a methodical strategy to minimize defects through six processes including choosing the manufacturer, gathering information, identifying the issues, analyzing the current situation, and coming up with solutions, putting the plan into action, data collection, and result analysis. The study investigates how quality, productivity, and cost aspects of a sewing line can be improved by implementing (TQM) approach in an apparel manufacturing industry in Bangladesh. This research concentrates on reducing four primary types of faults in the sewing department of DMC Apparels Ltd., such as uncut thread, up-down, broken stitch, and joint stitch. Proper information on several stitching errors was provided by the operators and helpers and those are used to assess the study in the next step. Performing the Pareto analysis and histograms to identify the primary concerns are part of the analyzing process. Moreover, using the 10 TQM pillars, the implementation step entails establishing the TQM mindset in the sewing line of the apparel industry. Several data-gathering methods are utilized to analyze primary data throughout the study’s final phase. To analyze the acquired data, Microsoft Excel was employed. The percentage of defect per hundred unit was decreased by 1.51% after optimization, as the recommended solutions’ impact on the defect level in the section was found to be quite significant. Significant parameters such as efficiency, quality, and cost aspect were analyzed and showed positive changes after implementing the TQM approach. The new technical layout also allows for the saving of five employees and a 3,000-min labor expense reduction. Finally, the research was completed by analyzing the basic pitch time graph and calculating the overall equipment effectiveness.