In order to explore the causes of subway construction accidents and prevent their occurrence, an analysis was conducted on 18 serious and above subway construction accidents in China from 2001 to 2022. Elements such as individuals, organizations, behaviors, equipment, and environment were extracted from subway construction accidents, and a network of subway construction accident causes was constructed based on this. The complex Network modeling and analysis tool Network X is used to measure network indicators such as node degree, shortest path, and intermediary centrality, combining the measurement results to conduct comparative analysis on key nodes and causal links in networks caused by serious accidents, major accidents, and catastrophic accidents. The results indicate that serious accidents are mainly caused by the superposition of management factors and equipment factors, as well as the superposition of management factors and illegal operation behavior factors. Major accidents are mainly caused by the combination of illegal operations and unfavorable geological conditions. Unfavorable geological conditions are the key factors for improving the level of accidents. Catastrophic accidents are mainly caused by the combination of organizational management factors and illegal operations, among which the lack of preparation of construction plans is the key factor for further escalation of accidents.