Abstract: With the continuous expansion of urban subway construction scales, the importance of safety risk management for tunnel construction is increasingly prominent. To address the common problems of complex causal chains between factors and unclear evolutionary mechanisms in current risk assessments of subway tunnel construction, this study constructs an evaluation index system from the perspectives of personnel, equipment, technology, environment, and management. The DEMATEL method is adopted to analyze the centrality and causality of each factor, clarifying their importance and causal attributes. Combined with the ISM method, a hierarchical structure diagram is established to clarify the hierarchical relationships among factors and the risk transmission paths. The research results show that the factors in subway tunnel construction interact with each other and are clearly hierarchical. Among them, A2 (construction standardization degree) is the core factor, playing a dominant role in risk formation; eight factors including E4 (management level of project managers) and E3 (hidden danger investigation and management) are indirect transmission factors; six factors including A3 (professional skill level) and D3 (surrounding pipelines and buildings) are direct factors that can directly induce accidents. Based on this, this study proposes a risk control strategy of "anchoring the risk source, blocking risk transmission, and guarding the final defense line", aiming to provide a theoretical basis and reference for risk management in subway tunnel construction.