This paper focuses on the auditor's decisions under the risk identification of complex supply chain network. We find that the disruption of supply chain operations of downstream enterprises significantly improves audit quality. Further mechanism test shows that global supply chain disruption impacts auditor engagement risk and finally improves audit quality. The heterogeneity test finds that above results is more significant in the samples with higher information technology capability, lower supplier concentration, auditor with higher industry expertise and large audit firms. The economic consequences test shows that under the impact of global supply interruption, the supply of high-quality audit can help reduce the synchronization of corporate stock prices and improve the pricing efficiency of capital market. The conclusion of this paper enriches the relevant research on the risk of supply chain system and audit quality, it also provides theoretical basis and experience reference for identifying risk propagation mechanism of complex supply chain network and enhancing supply chain competitiveness.