Today, the sustainability of any system in any industry has become one of the key strategies. The ultimate goal of sustainability is to improve environmental, economic, and social issues and other process improvements. Meanwhile, lead and zinc production is always accompanied by many environmental pollutants, and reducing pollution issues in this industry is inevitable. Therefore, planning to improve sustainability in the supply chain system of this industry is essential. Understanding the necessity of these measures, the present study has comprehensively evaluated the sustainable suppliers of the lead and zinc industry as one of the national industries and influential in improving the country's economic trend. The study method is "applied, primary, field-cross-sectional, and mixed" in terms of "purpose, data collection source, place and time of data collection, and data type". The statistical population includes industry experts who were used with a purposive sampling method from the opinions of 60 experts in the section of identifying factors affecting sustainable supply chain management and 30 experts in the section of evaluating factors and ranking sustainable suppliers of the industry. The methods used to identify and evaluate factors and suppliers are Fuzzy Delphi, Shannon Entropy and COPRAS, respectively. The Delphi analysis showed that seven key factors have high effectiveness in the industry. The entropy output indicates that the "social" index is in the first priority; and the "supervisory and legal", "economic" and "environmental" indices are in the second to fourth priorities. The COPRAS result also showed that the fifth, sixth and second suppliers are in the first to third ranks, respectively. Finally, practical and research suggestions were presented to the industry and researchers.