This study conducts a comprehensive and systematic investigation of the sources and uses of funds of the Social Security Organization by employing a grounded theory approach and multi-criteria decision-making analysis. The main objective of the research is to identify the factors affecting financial imbalance in this organization, which are classified into five categories: causal conditions, intervening conditions, contextual conditions, strategies, and consequences. In terms of purpose, the study is applied, and with respect to nature and methodology, it is classified as a descriptive–survey research. The statistical population includes managers and experts of the Social Security Organization, economists, and policymakers in the qualitative section, as well as senior managers, middle managers, and senior experts of the organization in the quantitative section. The qualitative sample consisted of 15 participants selected through purposive and judgmental sampling, while snowball sampling was used in the quantitative phase. The results obtained from aggregating expert opinions were analyzed using the fuzzy COCOSO method and indicate that contextual factors have the greatest impact on the sources and uses of funds of the Social Security Organization. Intervening conditions and causal conditions rank second and third, respectively. Through a multidimensional analysis, this study provides a comprehensive understanding of the financial crisis of the Social Security Organization and proposes a framework for the optimal management of its sources and uses of funds.