The primary objective of this research is to conduct a cluster analysis and classification of the Persian Gulf rim countries and Iran based on environmental indicators. In terms of purpose, application, and methodology, this study adopts a descriptive-analytical approach. Data collection was performed through documentary research and library-based methods. The geographical scope of this study encompasses eight countries: Iran, Bahrain, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates. To ensure precise and evidence-based analysis, raw statistical data for 52 environmental indicators were extracted from the World Bank database for the year 2023. The data processing and analysis were carried out in three operational stages: first, the OPA model was employed to determine the importance weights of each indicator for modeling; second, the CoCoSo multi-criteria decision-making method was utilized to rank the performance of the studied countries; and third, K-means clustering was applied to identify similarity patterns and classify countries into homogeneous groups. Statistical and computational analyses were executed using SPSS, GIS, and Excel software. The clustering results were visualized within a Geographic Information System (GIS) environment through zoning maps to better understand regional disparities. The findings indicate that, based on the ranking results, Bahrain, the United Arab Emirates, and Kuwait exhibit more favorable statuses compared to other regional countries, demonstrating more balanced performance across the investigated dimensions. Conversely, Iran obtained the lowest score and is positioned at a critical level, highlighting the urgent need to revise policies related to resource management, environmental protection, and sustainable development.