teachers beliefs have usually been left unattended in the realm of educational research in iranian context. one of those beliefs which seems to impact teachers performance in the classroom is their sense of self-efficacy, which refers to teachers belief in their ability to enhance student achievement and in bringing about positive learning outcomes. the present study aimed to investigate the probable effects of teachers efficacy beliefs on their instructional skills. fifty senior ma students and ma graduates in tefl from mazandaran university filled in a teacher efficacy scale (tes) questionnaire. after analyzing the tes, six teachers, three with the high and three with the lowest self-efficacy scores were selected for classroom observation. their classes were observed, audio-taped, transcribed, and analyzed both quantitatively and qualitatively to investigate their questioning patterns and their tendency to have group work in class. the results indicated that the high-efficacy group outperformed the low-efficacy group in terms of providing opportunities for students’ involvement in class activities to promote l2 learning. this implies that in teacher preparation courses, the teacher educators are not just to help teachers to gain the knowledge necessary for language teaching; they are to attend to the affective aspects of teacher preparation as well by, for instance, learning about and improving the teachers’ self-efficacy, wherever needed, for better performance