In the face of today’s global challenges, oil and gas companies must define long-term priorities and opportunities in implementing complex Arctic offshore projects, taking into account environmental, economic, technological and social aspects. In this regard, ensuring strategic sustainability is the basis for long-term development. The aim of the study is to analyze existing approaches to the concept of “strategic sustainability” of an offshore Arctic oil and gas project and to develop a methodological approach to assessing the strategic sustainability of offshore oil and gas projects. In the theoretical part of the study, the approaches to defining strategic sustainability were reviewed, and their classification was completed, and the most appropriate definition of strategic sustainability for an offshore oil and gas project was chosen. The method of hierarchy analysis was used for strategic sustainability assessment. Specific criteria have been proposed to reflect the technical, geological, investment, social and environmental characteristics important to the offshore oil and gas project. The strategic sustainability of 5 offshore oil and gas projects was analyzed using an expert survey as part of the hierarchy analysis method. Recommendations were made on the development of an offshore project management system to facilitate the emergence of new criteria and improve the quality of the strategic sustainability assessment of offshore projects in the Arctic.