Within the scope of this study, the relationships among alexithymia, psychological flexibility, authenticity and life satisfaction of individuals were investigated. In addition, the possible meditating role of psychological flexibility on the relationships among alexithymia, authenticity and life satisfaction were investigated. The research model is the relational screening model, which is one of the descriptive models that aims to examine the mediating role of psychological flexibility in the relationships among individuals' alexithymia, authenticity and life satisfaction. As the data collection tools, "Personal Information Form", "Toronto Alexithymia Scale (TAS-20)", "Authenticity Scale", "Psychological Flexibility Scale" and "Life Satisfaction Scale" were used. The sampling group of the study was composed of 702 adult individuals between the ages of 18 and 67Whilst analysing the data, SPSS 22 Package Program was used to highlight the relationships between variables (Pearson correlation coefficient) and mediation test. In the study, Bootstrap analysis and Sobel test were used to measure the statistical significance of the mediating effects of the model. According to the research findings, while there was a significant negative relationship between alexithymia and psychological flexibility variables and authenticity and life satisfaction variables, a positive significant relationship was found among psychological flexibility, authenticity and life satisfaction. According to the mediation test, psychological flexibility had a partial mediating role in the relationships among alexithymia, life satisfaction and authenticity. Alexithymia explained 52% of authenticity and 21% of life satisfaction through psychological flexibility. The present article discusses the abovementioned research results within the framework of the relevant literature, and suggestions are made accordingly.