In the context of globalization and resource constraints, embracing sustainable development has become a global consensus and an essential strategy for firms seeking to enhance their sustainable development capabilities, with the sustainable supply chain playing a crucial role in this process. This study employs an empirical approach to investigate the impact of the sustainable supply chain level, as measured by the ESG performance of other firms within the supply chain network, on the ESG of core firms, with the analysis focusing on Chinese listed firms from 2009 to 2022 and utilizing panel data models to assess the relationship. The findings indicate a positive correlation between the degree of sustainability of the supply chain network in which a firm is embedded and its ESG, and this positive correlation becomes stronger when the supply chain stability of the enterprise is higher. Heterogeneity analysis reveals a significant impact on non-dual-role and in regions with more favorable market environments. This study explores the transmission effects of ESG performance in the supply chain network, examining external factors affecting ESG. These findings provide valuable insights for firms in emerging economies, aiming to enhance their sustainable development practices.