<p>With the widespread dissemination of ESG principles, enhancing sustainable development performance has become a central corporate objective. This study examines how green trademarks, often viewed as marketing tools, function as strategic drivers of corporate ESG performance. Theoretically, we propose a framework that conceptualizes green trademarks as a credible, non-market signal of a firm’s long-term commitment to sustainability. We argue that this signal acts as a unique intangible resource, enabling firms to access critical resources and opportunities for sustainable development. Using data from Chinese listed companies from 2014 to 2023, we find that the cumulative number of valid green trademarks significantly improves corporate ESG performance, a result robust to various tests. Mechanism analysis reveals that this positive impact is channeled through three primary pathways: promoting green mergers and acquisitions, facilitating breakthrough green technological innovation, and enhancing ESG levels within the supply chain. Furthermore, this effect is amplified by executives’ green backgrounds, analyst attention and a corporate sustainability culture. Our primary theoretical contribution lies in integrating signaling theory with the resource-based view to explain how symbolic commitments (green trademarks) are translated into substantive actions and performance. We advance the literature by re-conceptualizing green trademarks from a market-facing label to a strategic antecedent of corporate sustainability transformation. These findings offer crucial insights for policymakers and managers aiming to leverage non-market strategies to foster genuine sustainable development.</p>