The challenging behaviours of children with autism spectrum disorder (ASD) have been widely described as one of the most significant sources of stress for teachers. However, less attention has been paid to the potential of teachers' perspectives as a source of knowledge to improve their practice. The purpose of this study was to explore teachers' experiences in managing the challenging behaviour of children with ASD. Specifically, we aimed to identify the perceived supports and barriers in their daily work routine. Using a snowball sampling procedure, 10 teachers from a segregated setting and general education schools were interviewed. Through thematic analysis, some themes were identified across participants, suggesting perceived barriers ("Behaviour misunderstanding," "Relationships," and "School administration") and perceived supports ("Challenging behaviour knowledge and expertise," "Human resources," and "School management"). In addition, the results demonstrated potential supports that could improve teachers' experiences ("Challenging behaviour specialisation," "Leadership team," and "Shared language and perceptions"). These findings have implications for the understanding of teachers' needs and may also inform the refinement and development of strategies to facilitate their work when managing the challenging behaviour of their students with ASD. The relevance of these findings for practice and further research are discussed.