The present study aimed to examine the mediating role of leader-member exchange in the relationship between motivational language and loyalty to supervisor. The population of this correlational study consisted of primary, secondary, and high schools in Gaziantep, Turkey during the 2020-2021 academic year. The research sample included randomly determined 511 teachers through unequal cluster sampling technique. In data analysis, descriptive statistics and correlation coefficients were estimated. Then, the model, which was based on the theoretical framework, was tested through structural equation modelling. According to research results, teachers’ perceptions of motivational language, loyalty to supervisor, and leader-member exchange were found to be relatively high. There were positive and high-level relationships between motivational language, loyalty to supervisor, and leader-member exchange. The results of structural equation modelling analysis indicated that the leader-member exchange partially mediated the relationship between motivational language and loyalty to supervisor. The research results revealed that the motivational language of school administrators was a significant determinant of teachers’ perception of leader-member exchange and their loyalty to supervisor. Thus, it seemed necessary to establish high-quality communication, appreciate their efforts, and support teachers to increase their loyalty to the administrator. Moreover, school administrators’ guiding teachers for their work, encouraging them using motivational language, and making them feel a sense of belonging and commitment to the school will positively affect teachers’ loyalty to the administrator.