Abstract: To facilitate targeted remediation efforts for abandoned open-pit mines and mitigate the adverse environmental impacts associated with open-pit mining, this study proposes a Fuzzy Comprehensive Evaluation (FCE) method for assessing the geological environment of such sites. A comprehensive evaluation index system is constructed by selecting 11 critical indicators across three distinct dimensions (geological conditions, resource destruction, and geological environmental issues). These indicators are identified through rigorous literature review and expert consultation. The Fuzzy Analytic Hierarchy Process (FAHP) is initially employed to determine the subjective weights of these indicators. However, a significant challenge encountered in practical FAHP application is the difficulty in rectifying fuzzy judgment matrices that fail to satisfy consistency requirements. To overcome this limitation, the problem of achieving a consistent fuzzy judgment matrix is transformed into a constrained optimization problem. The Improved Radial Movement Optimization algorithm (IRMO) algorithm is then introduced to efficiently search for the optimal solution to this problem. This integration leads to the development of the IRMO-FAHP method, specifically designed to derive optimal subjective weights, thereby enhancing the accuracy of the evaluation model. The precision and reliability of the IRMO-FAHP solution method were rigorously validated through three distinct case studies. Subsequently, the Entropy Weight Method (EWM) is applied to calculate the objective weights of the indicators, providing a data-driven counterbalance to the expert-derived subjective weights. Leveraging principles from game theory, these subjective (from IRMO-FAHP) and objective (from EWM) weights are then strategically combined to determine final comprehensive indicator weights, achieving a balanced integration of expert judgment and empirical data. Finally, based on the maximum membership degree principle, the Fuzzy Comprehensive Evaluation (FCE) methodology is applied to perform the overall assessment analysis. The practical application of this integrated IRMO-FAHP-EWM-FCE approach involved evaluating the geological environmental of four abandoned open-pit mines. The evaluation results consistently classify quarry a and clay mine d as "Class Ⅱ (Less Poor)" and quarry b and quarry c as "Class III (Poor)". These findings provide concrete reference benchmarks and valuable insights to directly inform and guide future geological environmental remediation and ecological restoration strategies for abandoned open-pit mines.