Abstarct: In recent years, teacher’s efficacy has drawn attention from several fields of study such as teaching context, material development, job difficulties, teachers` personalization and psychology. However, self-efficacy as a factor that represents teachers pragmatically especially in terms of issues which have not been practiced enough during pre-service is illuminating more and more. Thus, this study aimed to explore the EFL teachers' perceptions of their self-efficacy and the factors contributing to it. Following a qualitative research design, 11 Iranian EFL teachers were interviewed in this study to investigate the above-mentioned gap. According to the results, four main categories were elicited from the participants as elements influencing their self-efficacy: The top-ranked category was Personality, which was further comprised of three sub-categories of effective skills/approach, knowledge baxse, and teaching experience, all contributing to teachers’ self-efficacy; another main category elicited from the participants was that reportedly impede the development of teachers’ self-efficacy; the other major category was school support and collaboration between senior and novice teachers that can highly affect teachers' self-efficacy; finally, the last main category was the learner's performance that contributes to how teachers perceive their self-efficacy. The findings of this study not only contribute to the knowledge of elements influencing EFL teachers’ perception of their self-efficacy but also provide practical implications, namely early development of teacher self-efficacy through pre-service, as well as the creation of supportive career environments for teachers. After all, future studies were suggested to shed further light on this intersection by expanding the scope of the current research, employing mixed-method approaches, or investigating the possible role of gender and different groups on this topic.