PT X, a key player in the garment industry, faces operational challenges, including inefficient motion in packing and product defects. Current state analysis reveals a lead time of 3,424.90 seconds, with a value-added time of 3,054.90 seconds. Direct observations attribute motion wastage during packing to suboptimal hand movements, stemming from inadequate training in motion time measurement. The future state map proposes packing process improvements through motion time measurement, reducing time from 87.27 to 86.32 seconds, with a lead time of 3,423.95. From January to December 2014, total production reached 239,359 units, with 30,702 defective products. The main defect, stitch breakage in short-sleeved shirts ‘X,’ occurred 15,386 times. Current process capability stands at 3.690 Sigma. Using the 5W+1H method, addressing the root cause of stitch breakage reduced defects to 15,316, with process capability improving to 3.952 Sigma, a 0.262 improvement. Post-improvement analysis estimates an added value in quality costs at Rp1,943,297,372. Lean Six Sigma implementation aims to minimize defects and lead times, enhancing profitability.