Reservoir leakage is a critical issue that needs to be addressed in hydraulic engineering. It not only affects the normal water storage capacity during project operation but also poses a potential threat to the overall safety of hydraulic structures. Therefore, determining a reliable anti-seepage solution for the reservoir basin is of utmost importance. This study develops a comprehensive evaluation system for selecting anti-seepage solutions for pumped storage hydropower plants based on the combination of the Analytic Hierarchy Process (AHP) and Fuzzy Comprehensive Evaluation (FCE). The system covers five aspects: materials, environment, technology, safety, and economics, with a total of 5 secondary indicators and 15 tertiary indicators. The weights of each indicator are determined using the AHP method and combined with the fuzzy evaluation method to perform a quantitative evaluation of anti-seepage solutions, demonstrated through two case studies of pumped storage hydropower plants. The results demonstrate that the asphalt concrete panel bottom protection scheme is rated higher than the geotextile membrane bottom protection scheme, with the evaluation outcomes aligning with the actual conditions. The AHP-based fuzzy comprehensive evaluation method surpasses traditional prediction techniques by comprehensively integrating influencing factors and scientifically deriving their weights. This approach effectively mitigates the limitations inherent in conventional methodologies, especially regarding the management of multiple variables and intrinsic uncertainties, consequently yielding more robust and holistic assessment outcomes.