Listening strategies have been explored almost exclusively in contexts where second/foreign (L2) learners listen to audio-recordings. The limited research in understanding teacher input in the classroom is unjustified given how pervasive teacher talk is, particularly in Asian contexts. This area of research is even more scarce in the increasingly popular content and language integrated learning (CLIL) classroom, where students learn content subjects (e.g., science) through their L2. Considering its dual focus on content and L2 learning, it would be interesting to investigate whether CLIL learners may deploy some new listening strategies and how much they are drawing upon their top-down (more meaning-focused) and bottom-up (more language-focused) processing strategies. This study sets out to explore how learners deploy listening strategies to understand teacher talk in the CLIL biology classroom in Hong Kong. Data was collected through lesson observations and stimulated recall interviews with grade 11 students. Findings reveal that students deploy some novel strategies which are more relevant to the CLIL classroom (e.g., decoding subject-specific terminology by breaking down "biodiversity" to "bio" + "diversity"), and these strategies include both top-down and bottom-up ones. There are some teacher-aided strategies such as aided selective attention, which involves the teacher explicitly prompting students to attend to certain keywords. This study, therefore, highlights the interactive nature of listening to the teacher input in the CLIL classroom and the pivotal role of the teacher in achieving the dual goal of content and language learning. Pedagogical implications and professional development in CLIL are highlighted. Copyright © 2020 AsiaTEFL.