Given the recruitment and retention crisis within the teaching profession, it is essential that the factors contributing to this are examined. Studies suggest that there has been a general decline in teacher wellbeing since the onset of the COVID-19 pandemic, and student conduct problems are known to be a key negative contributor to poor teacher wellbeing. This study examines how student conduct problems influenced teachers' wellbeing following the onset of the COVID-19 pandemic. Specifically, it explores the extent to which student behaviour was seen as changing during the pandemic, and how this may have had an impact on teachers' wellbeing. Nine participants took part in this study. All the participants were teachers in schools in England (four primary and five secondary; nine female). The data were collected via semi-structured virtual interviews. Using a qualitative approach, the study undertook an in-depth analysis of the interview data using Interpretative Phenomenological Analysis. The findings suggest that the teachers experienced an increase in student conduct problems following the onset of the pandemic and that this negatively affected wellbeing for some. The teachers also reported an increased need for student support and differential needs for different groups of students. It is important that consideration is given as to how teachers can be effectively supported to manage student conduct problems and the potential impact of these on their wellbeing, particularly since the onset of the pandemic.