选取2007~2022年2 369家A股制造业上市公司数据，检验高铁开通对企业高质量发展的影响。研究发现，高铁开通显著促进了企业高质量发展。机制分析表明：高铁开通可以通过降低供应链依赖来促进企业高质量发展，且主要是降低下游客户依赖；同时，在环境不确定性较高的情境中，企业降低供应链依赖的行为倾向更明显。异质性研究显示，对于非国有企业、高科技行业、处于供应链政策环境和数字政策环境较差地区的企业，高铁开通对企业高质量发展的促进作用更显著。进一步研究发现，企业降低供应链依赖有利于促进企业绩效稳定性和加快供应链上的资金流动效率，但也伴随着产品流动效率的损失。

Using data from 2369 A-share listed manufacturing firms from 2007 to 2022, this study empirically examines the impact and mechanism of the opening of high-speed rail (HSR) on the high-quality development (HQD) of firms. The study finds that the opening of HSR significantly contributed to the HQD of firms. The mechanism test found that the opening of HSR can promote the HQD of firms by reducing supply chain dependence, and mainly by reducing downstream customer dependence. Meanwhile, the behavioral tendency of firms to reduce supply chain dependence is more obvious in the scenario of higher environmental uncertainty. Heterogeneity studies show that for non-state-owned firms, high-tech industries, and firms in regions with poor supply chain policy environments and digital policy environments, the opening of the HSR has a more significant effect on the promotion of HQD of firms. Further research finds that firms’ reduction in supply chain dependence is beneficial in promoting firm performance stability and accelerating the efficiency of financial flows along the supply chain, but it is also accompanied by a loss of product flow efficiency.