Although a significant body of research on instructional leadership has been carried out in Western societies, few empirical studies have only recently been carried out in the developing and non-western societies. The present study was carried out to shed more light on leadership research in Iran, in which previous empirical studies on principal instructional leadership are very few. In so doing, the present study was set to explore the relationship between principal instructional leadership, teacher collective efficacy, and job satisfaction in Iranian primary schools. In fact, the current study sought to understand how principal instructional leadership and teacher collective efficacy influence job satisfaction in Iran. Survey data collected from 292 teachers were analyzed using confirmatory factor analysis and structural equation modeling (SEM). This study employed a cross-sectional, survey research design. Data were collected from teachers in 12 public primary schools in Kurdistan province. The schools included grades 1- 5. Data were collected in fall semester of the academic year 1396/1397. A letter of invitation, consent form, and the survey package were given by hand or sent electronically to teachers in the schools. Participants were given one week to respond to the questionnaire. The sample of respondents consisted of 193 males and 99 females. Three instruments were used to collect the required data for the present study. Principal Instructional Leadership (PIL) was measured by the 50 item version of the Principal Instructional Management Rating Scale-Teacher Form (PIMRS; Hallinger, 1982, 1990, 2015). It should be noted that the PIMRS does not measure ‘leadership effectiveness’, but rather the degree of role engagement. Collective Teacher Efficacy (CTE) was measured by a twelve-item scale developed by Goddard and colleagues (Goddard et al., 2000) and adapted by Leithwood (2010). The scale employed a seven-point Likert scale ranging from 1 (Strongly Disagree) to 7 (Strongly Agree). Job satisfaction was measured with two items from Carpara et al. (2003) on a 9-point scale, ranging from strongly disagree to strongly agree. The researchers followed Brislin’s (1970) backwards translation method for translating the surveys from English to Persian. The original English versions were first translated into Persian by a professional translator. Then, the Persian version was translated back into English by a second native speaker who was unfamiliar with the original version. The two versions were then compared, discrepancies identified and discussed, and refinements made to the Persian version. The researchers also rephrased some items to ensure their suitability for Iranian educators without altering the original meaning. Although each of these instruments had been subject to extensive testing for psychometric properties in previous research, we tested the measurement properties of the Persian translated version of the three instruments in order to validate their use in the Iranian context. Reliability was measured with Cronbach's alpha test of internal consistency. Construct validity of the scales was assessed through confirmatory factor analysis (CFA). The results substantiated the hypothesized conceptual model suggesting positive relationships among principal instructional leadership, collective teacher efficacy and teacher job satisfaction. It was also revealed that principal instructional leadership had a positive effect on collective teacher efficacy and teacher job satisfaction. In other words, teachers will have more commitment, professional engagement, and job satisfaction when they find their school managers' educational management behaviors appropriate. The findings of the present study will offer theoretical and pedagogical implications for school leadership in Iran. It also adds to the existing body of research on the effects of principal instructional leadership in non-Western, developing societies It is thought that teachers' perceptions of collective efficacy are related to school principals' leadership behaviors. School leadership comprises influencing and directing the school staff to accomplish common objectives (Leithwood & Reihl, 2005). The sense of collective efficacy can develop in teachers, depending on school leadership behaviors (Ross & Gray, 2006). Collective efficacy beliefs are expected to increase as school leaders increase the sense of efficacy in teachers and their beliefs that they can improve the quality of education as a group. In this respect, because it is thought that teacher self-efficacy and school leadership behaviors are related to collective teacher efficacy, the relationship between these constructs seems to be logical. In other words, as school principals' effective leadership behaviors increased, teachers' collective efficacy beliefs also increased in their schools. At the same time, school principals' effective school leadership behaviors positively and significantly predicted collective teacher efficacy. These findings of the study are partially in line with those that report a relationship between school administrators' different leadership behaviors and collective teacher leadership (Brinson & Steiner, 2007; Calık et al., 2012). Strong leadership facilitates teacher collaboration and enables teachers to overcome difficulties (Bandura, 1993). School leadership pertains to influencing and directing others for the accomplishment of common objectives to improve the quality of education at school (Leithwood & Reihl, 2005). Enhancing teachers' collective efficacy is related to improving certain organizational and personal characteristics. Bandura (1997) stated that collective efficacy and self-efficacy are fed from similar sources. These sources include experiencing success, others' experiences, verbal persuasion, and affective states; the most important of these sources is experiencing success. Therefore, practices that support these sources can be said to increase teachers' collective efficacy. In this regard, there are studies that explain the influence of leadership behaviors on collective teacher efficacy. Accordingly, school leaders rewarding teacher success and featuring the achievements at school (Marzano et al., 2005), activities related to organizational learning, and conversations with teachers about ensuring student achievement (Bandura, 1997) strengthen perceptions of collective efficacy. Collective teacher efficacy is a promising construct for promoting understanding of ways schools can foster student achievement (Tschannen-Moran & Barr, 2004, p. 189). Functioning as a group-related perception and a school-level variable, collective teacher efficacy is concerned with teachers’ beliefs and perceptions of the effectiveness of their school as a whole and their collective perceptions of the ability to exert positive educational differences to the learners (Goddard & Goddard, 2001). Playing the same role as self-efficacy beliefs do in individual’s performance, collective efficacy affects collective performance in a variety of fields such as business, sports, politics, and education. Teachers’ collective efficacy is conceptualized as the beliefs teachers hold towards their collective competencies to positively change the functioning of their learners (Bandura, 1993). Furthermore, school administrators' practices in enhancing teachers' skills improve teamwork (Supovitz & Christman, 2003), and their support of teachers to overcome problems at school and including them in the decision-making process are of great importance in the development of collective efficacy (Brinson & Steiner, 2007). Leithwood (1993) stated that leaders' contributions to the school sets the tone of a school culture that can develop teacher collaboration and a collective identity. School leaders raising a powerful vision reveal collective leadership.