?eachers' interpersonal behaviour is considered important for the quality of the student--teacher relationship. The present study examined teachers' and students' perceptions regarding teachers' interpersonal behaviour and the degree of their agreement at the class level. Moreover, this study investigated whether possible differences between them are associated with the teachers' and classes' characteristics. Participants were 1669 students and 43 secondary teachers within 85 secondary classrooms in Greece. The Greek version of the Questionnaire on Teacher Interaction was used to assess eight aspects of teachers' interpersonal behaviour. A high degree of divergence between teachers' self-perceptions and students' perceptions about their teachers' interpersonal behaviour was found. Multiple regression analyses showed that the differences among teachers' and students' perceptions can partially be explained by teachers' years of teaching experience and the degree level, as well as the class educational level. Findings of this study provide specific practical implications.