In this study, it was aimed to reveal the relationship between school administrators‘ leadership styles and teachers’ organisational stress levels. In addition, school administrators‘ leadership styles and teachers’ organisational stress levels were examined in terms of some demographic variables. The study is a quantitative research and is in relational survey model. Teachers working in public primary schools in Şahinbey and Şehitkamil districts, which are the central districts of Gaziantep, constitute the population of the study. The sample of the study consists of 422 teachers selected from this universe using the convenience sampling method. The data of the study were obtained with a data collection tool consisting of three parts: ‘Personal Information Form’ created by the researcher, ‘Organisational Stress Sources Scale’ created by Pehlivan (1993) and ‘School Principals Leadership Styles Scale’ created by Akan, Yıldırım and Yalçın (2014). Descriptive statistics, t-test, ANOVA and Pearson correlation tests were used to analyse the data. As a result of the analysis of the data, teachers' organisational stress levels were found to be moderate. As a result of the analyses made with demographic variables, it was determined that organisational stress differed significantly according to seniority and number of teachers in the school. According to the perceptions of the teachers, leadership styles of school principals differed significantly according to age, seniority and number of teachers in the school. It was found that there was a moderate negative relationship between teachers' organisational stress levels and transformational leadership, a moderate positive relationship with laissez-faire leadership, and a weak positive relationship with transactional leadership. Transformational leadership style predicts 27.4% of the organisational stress perceived by teachers. Studies that will reveal the cause and effect relationships between teachers‘ organisational stress and school administrators’ leadership styles can be designed with qualitative or mixed methods.