This study was conducted in English for Academic Purposes (EAP) context to explore Iranian teachers' perceptions of their pedagogical content knowledge (PCK) and their sense of professional identity (PI) as well as to scrutinize how their cognitions were practiced in EAP classes. To this end, two ELT teachers and two content instructors (i.e. subject experts who teach EAP courses in addition to their specialized field of study) from a university in Tehran participated in the study and their classes were observed for a full academic semester. To thoroughly probe the teachers' cognitions, semi-structured interviews were also conducted. The results of content analysis indicated some commonalities but major discrepancies in the cognitions and practices of the two pairs of teachers with regard to their PCK. Teachers of both camps claimed to have interactive EAP classes where group work is highly appreciated and students' questions are welcomed. Attending to their discrepancies, the content instructors seemed to adhere to 'transformative' education by reflecting on their teaching, hearing learners' voice, being responsive to their learning needs, and encouraging teacher-learner collaboration. On the other hand, the ELT teachers reflected a more 'traditional' approach, leaving behind issues of flexibility and innovation in their teaching methods. As far as the EAP teachers' PI is concerned, the study came up with eight factors as the underlying constituents of their PI. It was also found that pedagogical content knowledge and professional identity are interrelated attributes of EAP teachers. The findings provide implications for syllabus designers as well as EAP teacher education.
