Abstract: Based on the perspective of supply chain transmission, this article adopts the Broadband China strategy as a quasi-natural experiment to analyze the network spillover effect of digital infrastructure. Research has found that selecting the location of the largest customer as a demonstration city for Broadband China will increase suppliers' revenue. Mechanism analysis shows that the network spillover effect of the Broadband China strategy is mainly achieved through accelerating knowledge spillover and reducing transaction costs. Heterogeneity analysis shows that non-state-owned suppliers and non-manufacturing suppliers are more susceptible to spillover effect. In addition, the improvement of digital infrastructure level in the region where the supplier is located can further enhance the spillover effect. The research conclusion of this article provides new empirical evidence for strengthening digital infrastructure construction to promote enterprise development.
