private sector investment is recognized as one of the key mechanisms for sustainable financing, reducing the financial burden on governments, and enhancing the efficiency of civil projects in less developed regions. This investment not only provides financial resources but also introduces advanced technologies, technical knowledge, efficient management models, and greater transparency, thereby addressing common challenges in urban construction project management such as delays, excess costs, and low quality. In Chabahar, as a strategic free trade zone with high potential for port and infrastructure development, examining the impact of this type of investment on construction management efficiency appears essential. In this applied and descriptive-survey research, the effect of private sector investment on the efficiency of urban construction project management in Chabahar was evaluated. The statistical population consisted of 120 managers and experts involved in urban projects, from which 92 individuals were selected through purposive random sampling. Data were collected using a standard 70-item questionnaire (five-point Likert scale) and analyzed with SPSS and SmartPLS software (partial least squares method). The validity and reliability of the instrument were fully confirmed. The results indicated that private sector investment has a strong positive and significant impact on construction management efficiency. The greatest effects were observed from the components of improving executive standards and accelerating execution time, while other components (project financing, reducing government financial burden, technology and technical knowledge transfer, increasing resource productivity, and enhancing financial transparency) also showed positive and significant effects. The findings emphasize the priority of executive quality and scheduling in Chabahar's urban policy-making and recommend that the development of public-private partnership models (PPP/BOT) and transparency systems be prioritized.