Justifications for promoting learner autonomy in language learning are manifold. As teachers have a central role in developing learner autonomy and given the influence teachers’ beliefs have on their practices (Borg, 2006), it is essential to gain insight into their views regarding learner autonomy (Borg & Al-Busaidi, 2012). Similarly, learners’ perceptions concerning language learning influence their openness to the ideas presented in the language classroom (Cotterall, 1995). Furthermore, as mismatches between teachers’ and students’ beliefs could have a negative impact on learners’ motivation, understanding the relationship between teachers’ and students’ beliefs might lead to more successful learning. The present study explored language teachers’ and learners’ beliefs and classroom practices concerning learner autonomy in a Hungarian secondary school. Mixed methods were used: attitude-questionnaires and interviews revealed what language teachers (n=9) understood by learner autonomy and in what ways they claimed that they incorporated it in their practice. The study also looked into language learners’ beliefs (n=100) and reported autonomous behaviours. A questionnaire explored to what extent students felt responsible for their autonomy in language learning. Furthermore, classroom observations helped to gain insight into teachers’ classroom practices and language learners’ autonomous behaviours. Finally, the study revealed correspondences and mismatches between teachers’ and students’ autonomous beliefs. The findings of the study have pedagogical implications for practicing teachers and teacher educators as their awareness should be raised about the importance of learner autonomy to help them shape their learners’ learning experiences positively regarding autonomy development.