This research aimed to analyze quality control to reduce appearance defects in piano products at PT. Musical Instruments using the Six Sigma methodology with the DMAIC approach. The main issue was the high level of product defects, which affected product quality and customer satisfaction. The study identified five main factors contributing to appearance defects: incompatibility with work methods, lack of worker training, use of non-standard materials, suboptimal jig conditions, and unsupportive working environments. To address these issues, the study proposed improvements such as enhancing standard operating procedures, regular worker training, using high-quality materials, regular maintenance of jigs, and improving work environment conditions. These improvements were expected to reduce appearance defects, improve product quality, and meet the company's quality standards. The research used quantitative data on the number of production defects and analyzed the causes using a fishbone diagram with 4M + 1E factors. The study also calculated the Defects Per Million Opportunities (DPMO) and determined the sigma level of the production process, which was found to be 2.77. This indicated a need for further improvements to reduce defects. The analysis revealed that scratch defects were the most common, accounting for 41% of all defects. The study also used a Pareto diagram to prioritize defect types and a p-control chart to monitor defect proportions over time. The study concluded that implementing the proposed improvements, such as stricter operator supervision, regular training, and better maintenance of jigs and materials, would help reduce defects. Additionally, maintaining a clean and well-lit work environment and following 5S practices were recommended to ensure long-term quality improvements. The research provided actionable recommendations to enhance product quality and operational efficiency at PT. Musical Instruments.This research aimed to analyze quality control to reduce appearance defects in piano products at PT. Musical Instruments using the Six Sigma methodology with the DMAIC approach. The main issue was the high level of product defects, which affected product quality and customer satisfaction. The study identified five main factors contributing to appearance defects: incompatibility with work methods, lack of worker training, use of non-standard materials, suboptimal jig conditions, and unsupportive working environments. To address these issues, the study proposed improvements such as enhancing standard operating procedures, regular worker training, using high-quality materials, regular maintenance of jigs, and improving work environment conditions. These improvements were expected to reduce appearance defects, improve product quality, and meet the company's quality standards. The research used quantitative data on the number of production defects and analyzed the causes using a fishbone diagram with 4M + 1E factors. The study also calculated the Defects Per Million Opportunities (DPMO) and determined the sigma level of the production process, which was found to be 2.77. This indicated a need for further improvements to reduce defects. The analysis revealed that scratch defects were the most common, accounting for 41% of all defects. The study also used a Pareto diagram to prioritize defect types and a p-control chart to monitor defect proportions over time. The study concluded that implementing the proposed improvements, such as stricter operator supervision, regular training, and better maintenance of jigs and materials, would help reduce defects. Additionally, maintaining a clean and well-lit work environment and following 5S practices were recommended to ensure long-term quality improvements. The research provided actionable recommendations to enhance product quality and operational efficiency at PT. Musical Instruments.