Current research on the supply chain risks of prefabricated construction mainly treats risk factors as isolated points, lacking a comprehensive analysis of the interplay between these factors. This study took a stakeholder perspective and a full lifecycle approach, employing the SCOR model to identify risk factors. A risk assessment model based on social network analysis was constructed to investigate the risk factors and their interactions in the supply chain of prefabricated construction. By calculating various SNA indicators, key risks and critical relationships were determined. Finally, risk control measures were proposed and the effectiveness of risk response was evaluated. This research provides an effective method for evaluating and mitigating supply chain risks in prefabricated construction, enhancing the effectiveness and accuracy of risk control for all stakeholders involved.