Research into critical thinking has witnessed its role in students’ foreign language learning, including English. Of components contributing to students’ critical thinking development, teachers are the ones who engage students in thinking about or making judgment of what they are doing in their learning process. As critical thinking and language skills are known as intertwined, argumentative essays allow students to reflect on their own writing. However, research on teachers’ perceptions and practices of the interplay between students’ critical thinking and argumentative essays is still meagre. This paper therefore examines this area of interest. Data collected in this study include a questionnaire and semi-structured interviews. Participants were 85 teachers at a university in the Mekong delta, and six participated in the interview process. The findings reveal that teachers’ perceptions of students’ critical thinking regarding interpreting, analysing, inferencing, evaluating and self-regulating were at a high level. Debates and group discussion were the two activities teachers used most in writing classes. Pedagogical implications and recommendations are made to foster students’ critical thinking skills.

 Keywords: critical thinking skills, teachers’ perceptions, argumentative essay writing