In this VUCA era, investigating the impact of supply chain concentration on enterprise resilience holds significant theoretical and practical value. Using panel data from Chinese A-share listed companies (2012–2024), we find that high supply chain concentration significantly undermines enterprise resilience, and the conclusion remains robust after a series of robustness tests and endogeneity treatments. Mechanism analysis shows that financing constraints, innovation capability, and risk-taking act as important mediating channels. Furthermore, nonlinear analysis identifies structural dual-threshold effects associated with industry competition intensity and business environment quality, suggesting that the adverse effect of supply chain concentration on enterprise resilience varies across different threshold intervals. Heterogeneity analysis further shows that this negative impact is more pronounced in enterprises with weak internal management, low levels of digitalization, or excessive ESG greenwashing, as well as in external contexts such as less-developed regions, low regional data factorization levels, or non-high-tech industries. This study provides micro-level empirical evidence for understanding the strategic trade-off between supply chain structure and enterprise resilience and provides a reference for policy makers to improve the resilience and security of industrial chains.