Lesson Study is considered as a way of improving teachers’ professional development in foreign language teacher education courses. Integration of collaboration with focused observation within Lesson Study facilitates teacher professionalization and pedagogical practice. Therefore, this study aimed to explore Iranian EFL teachers’ perceptions of the practical implementation of Lesson Study, and examine novice and experienced EFL teachers’ comments about merging their theoretical knowledge with practice throughout the application of Lesson Study. To this end, four novice and three experienced language teachers, both female and male were selected as the participants of this study. Data collection was done through triangulation of teachers’ reflective notes, an unstructured interview, observation, and field notes. The findings indicated that EFL teachers have positive views toward Lesson Study as a means of professional development. Additionally, the novice and experienced EFL teachers have different attitudes regarding lesson planning, reflective teaching, and collaborating with other colleagues. The findings of this study can have implications for EFL teachers and teacher educators to promote ongoing learning in their profession through reflective teaching and collaboration.
