Depression is one of the most common mental disorders, having a significant impact on quality of life. From 1990 to 2010, it was recognized as the most costly mental illness worldwide. Estimates indicate that more than 17% of the U.S. population experience depression at some point in their lives, and each year, 19 million individuals develop major depression.

In recent years, attention to psychological factors influencing the health and performance of female physical education teachers has increased. Among these factors, optimism can play an important role in enhancing psychological flexibility. The present study aimed to investigate the predictive role of optimism in psychological flexibility among female physical education teachers in Shiraz. This research was descriptive–correlational and applied in nature. The statistical population consisted of 300 female physical education teachers, of whom 140 were selected using cluster sampling. Data collection tools included three standardized questionnaires: the Psychological Flexibility Scale by Dennis and Vander Wal, and the Academic Optimism Scale by Beard et al. Data were analyzed using SPSS version 24 with Pearson correlation and multiple regression tests.

The findings revealed a positive and significant relationship between optimism and psychological flexibility. Furthermore, multiple regression analysis showed that the two variables could simultaneously predict psychological flexibility. The results indicate that optimism can contribute to enhancing the psychological resilience of female physical education teachers. Based on these findings, it is recommended that educational and counseling programs be designed and implemented to strengthen these factors, thereby facilitating improvements in teachers’ mental health and professional performance.