In recent years, the recurrence of product-quality trust crisis has raised serious concerns about the integrity of China’s product markets and the efficacy of its regulatory systems. These events have not only impeded the growth of domestic enterprises and tarnished the international reputation of Chinese manufacturing, but also exhibited signs of spillover into the capital markets. Against this backdrop, it becomes imperative to systematically assess the economic ramifications of such crisis from a capital market perspective and explore potential mitigation mechanisms. This paper fills this gap by examining the micro-level risk spillover effect of product-quality trust crisis on corporate financing constraints in China. Leveraging a unique dataset that integrates annual financial statements of A-share listed companies from 2007 to 2021 with firm exposure data derived from CCTV 3.15 Gala, it identifies a sample of firms either directly or indirectly involved in such crisis. To enhance analytical precision, this paper establishes a relationship-based identification framework that traces spillover through three key channels: equity ties, supply chain relationships, and administrative affiliations. Using panel regression techniques and a battery of robustness tests, the findings indicate that product-quality trust crisis exacerbates the financing constraints of affected companies, manifesting in higher financing costs, shorter financing durations, and increased difficulty in financing. Furthermore, the crisis intensifies financing constraints through worsened corporate financial performance, increased government penalties, and altered investor perceptions. Although effective public relations, social responsibility performance, diversification strategies, and recognition from the capital market and government can alleviate financing constraints to some extent, they cannot completely eliminate the negative effect of the crisis. By elucidating how product-quality trust crisis cascades from the real economy into the financial system, this paper contributes to the literature on corporate risk management, investor behavior, and regulatory oversight. The results offer practical insights for firms aiming to bolster quality governance, for investors seeking to manage exposure to non-financial risks, and for regulators committed to fostering a more resilient and trustworthy market environment. Ultimately, this paper underscores the urgency of early intervention and coordinated risk management strategies to prevent isolated quality incidents from triggering broader financial instability.