Trends in academic curricula worldwide have highlighted the need for language learners to develop critical thinking skills for academic and social success. However, there are few studies on what EFL teachers think of critical thinking and how they incorporate it into their teaching. This case study aimed to provide an overview of Taiwanese EFL teachers’ awareness and perceptions of teaching and promoting critical thinking skills. Four experienced EFL teachers participated in this study. Data were collected through semi-structured interviews and classroom observations. The results indicated that these teachers were optimistic about incorporating critical thinking into language teaching and used various strategies to encourage students to think critically. However, teachers also reported that they found it difficult and encountered obstacles due to learners’ language levels and contextual factors. Accordingly, these teachers expressed the need for professional development in order to provide effective instruction that guides their students in critical thinking.