This study aims to determine the effect of the principal's transformational leadership on the performance of teachers at Mdrasah Aliyah Ghoyatul Jihad, Karawang Regency. This study used a quantitative approach, correlative survey method with 23 respondents. Using saturated sampling and data collection techniques using an instrument in the form of a questionnaire. Data analysis used descriptive analysis using SPSS version 16.0 Windows software. The results showed that there was a positive and significant effect of transformational leadership on teacher performance with a Pearson correlation level of 0.848. The correlation was very strong. so that it can be interpreted that if there is a positive change in the transformational leadership score of one unit it will make a positive change in teacher performance. Based on the results of this study, it can be concluded that transformational leadership has a positive effect on teacher performance.