Given the pivotal role that roads play in a nation's development, their construction often entails significant risks and challenges. Therefore, road construction projects must be successfully implemented. Numerous studies have been conducted to discover the key factors affecting road construction projects and their improvement. The aim of this study was to examine and pre-determine the factors affecting the success of road construction. Data was collected from experts in the field of road management to identify the factors influencing road construction projects in Iraq. Data was also used from interviews with road construction project managers. After analyzing this data, the study concluded that there are several external and internal constraints that affect project success. These constraints include site preparation, implemented infrastructure, land ownership restrictions, technical design constraints, administrative constraints, financial constraints, and security constraints. A plan-based analysis revealed that the highest percentage of constraints was related to technical design (22%). The study recommended addressing these constraints proactively to avoid future problems during project implementation while increasing the accuracy of planning and managing bills of quantities to reduce change orders. While ensuring cash flow for projects to avoid delays, the availability of skilled labor is also essential. This work contributes to existing knowledge by providing academics and project management experts with an additional set of variables to consider when attempting to predict the outcomes of road construction projects. Project managers and stakeholders in Iraq can benefit from the study's findings to enhance the likelihood of success of road construction projects.