Students' non-compliant classroom behaviour is mentioned as one of the biggest challenges for teaching. This study examines the non-compliant behaviour of secondary school students and its predictors. Data were obtained from a longitudinal sample of 639 secondary school students in Austria (Styria). Students filled out a paper-pencil questionnaire at the end of the 7th grade (mean age = 13.5 years, SD = 0.61) and 8th grade. Non-compliant classroom behaviour was assessed using a 15 item self-rating scale. First results indicate that boys show more non-compliant classroom behaviour than girls. Students with hyperactivity stated to show more non-compliant classroom behaviour than students without hyperactivity. However, students with and without emotional problems as well as students with and without learning problems did not differ in their self-rated non-compliant classroom behaviour. Findings of multi-level analyses showed that more positive student--teacher relation is linked with less non-compliant classroom behaviour for both girls and boys. As non-compliant classroom behaviour is a relatively stable characteristic of both male and female students, it is important to intervene as early as possible. In addition, schools should take classroom compositions into account and make teachers aware of the high importance of the student--teacher relation for students' behaviour.