The growing complexity of civil infrastructure projects and the increasing exposure of critical facilities to both natural and human-induced threats have highlighted the importance of integrating passive defense principles into construction management. Passive defense encompasses a set of non-aggressive measures aimed at reducing the vulnerability of infrastructure, enhancing resilience, and ensuring the continuity of essential services without relying on active military intervention. This study investigates the relationship between passive defense strategies and construction project risk management in civil engineering projects located in Ramsar, Iran. A quantitative correlational research design was employed. Data were collected from civil engineering professionals working in 12 construction companies. Based on Cochran's sampling formula, 58 experts were selected as the research sample. The collected data were analyzed using descriptive statistics, correlation analysis, and multiple linear regression to examine the effects of passive defense components on construction risk management performance. The findings indicate that passive defense measures—including camouflage, concealment, deception, protective covering, appropriate site selection, spatial dispersion, functional segregation and relocation, structural fortification, resilient structural design, and emergency information management—have a statistically significant and positive influence on the effectiveness of construction project risk management. Among these factors, resilient structural design and fortification exhibited the strongest predictive effects on improving project resilience and minimizing operational risks. The study concludes that incorporating passive defense principles into construction planning and project management frameworks can substantially enhance the safety, sustainability, and resilience of civil infrastructure. The findings provide practical guidance for engineers, project managers, and policymakers seeking to strengthen risk management strategies in critical construction projects.