In today’s highly competitive business environment, sustainability performance in enterprises emerges as an important factor with environmental, economic, and social dimensions. Sustainability performance elements such as air, soil, and water pollution, traffic accidents, industrial accidents, oil/chemical pollution, and waste management are considered priority practices that take into account a more livable environment and future generations. The perspective of society, governments, and enterprises on these practices is increasingly gaining importance and is seen as indispensable. However, identifying sustainability performance elements in port operations is necessary, as it is considered important for raising awareness economically, socially, and environmentally. Accordingly, identifying sustainability performance elements in port operations has become not an option but a necessity. However, in the existing literature, sustainability performance elements are addressed in a limited way and are not sufficiently emphasized. To fill these gaps, this study proposes the Interval-valued p,q,r-Spherical Fuzzy SIWEC model. The Interval-Valued p,q,r-Spherical Fuzzy SIWEC method is a decision-making technique that helps achieve more accurate and reliable results in uncertain situations. Within the scope of the study, “Revenue Management and Taxes” has been identified as the most important sustainability performance element.