This exploratory study examined whether pre-service teachers' professional commitment and sense of efficacy significantly predict their perceptions of unethical teacher behaviours. Specifically, the present study aimed to uncover the factors influencing pre-service teachers' ethical stances that potentially shape their actions regarding the challenging aspects of the teaching profession during the early phases of their career. Correlation and structural equation modelling analyses were conducted to analyse the data reliably. The results showed that pre-service teachers' planned efforts significantly predicted the sense of efficacy in addition to their perceptions of 'offensive and discriminative teacher behaviours' and 'irresponsible and dishonest teacher behaviours'. Additionally, pre-service teachers' sense of efficacy significantly mediated the relationship between career development aspirations and perceptions of 'irresponsible and dishonest teacher behaviours'. The results suggest that considering pre-service teachers' professional commitment with a sense of efficacy can provide a comprehensive framework for understanding pre-service teachers' ethical stances on unethical teacher behaviours.