This study aims to determine and analyze the effect of transformational leadership style on employee performance with job stress as an intervening variable. This research uses descriptive quantitative research methods. The population in this study were all employees of PT. Pos Indonesia (Persero) Bandung Head Office in the Directorate of Human Resources. The sample in this study used a saturated sample of 65 employees. The data consists of primary and secondary data. Data analysis was performed by path analysis, hypothesis testing and coefficient of determination. This study indicates that the transformational leadership style variable (X) has a significant effect on employee performance (Y) by 48.3 percent. Meanwhile, the variable transformational leadership style (X) has no significant effect on job stress (Z), the job stress variable has no effect significantly on employee performance (Y), and the transformational leadership style variable (X) has a significant effect on employee performance variables (Y) through job stress (Z) by 71 percent.