The study aimed to identify the impact of international project management standards on project quality in public and private sector organizations in Oman. The study followed an analytical descriptive approach, and the questionnaire has been used as a tool for collecting data from simple random sample size 416 individuals. The study showed that the quality level of projects implemented by private sector institutions is higher than those implemented by public sector institutions. The study also identified a beneficial effect of various aspects of international project management standards—specifically in the areas of project communication management, project scope management, project integration management, and project stakeholder management—on the quality of projects within public and private sector organizations in the Sultanate of Oman, The absence of a beneficial influence from the aspects of international project management standards—such as project procurement management, project resource management, and project time management—on the quality of projects within these organizations is evident. The study offered several recommendations, including: The need to rely on standard costs to complete the project efficiently, and work to involve workers and stakeholders in the preparation of strategic plans for the project.