This study was carried out to investigate the relationship between job characteristics, perceived organizational justice, and organizational commitment among the staff of the Ministry of Education in Mazandaran Province. The design of this descriptive, applied research was correlational. The statistical population of the study consisted of all employees of the General Directorate of Education in Mazandaran Province in 2017 (340 individuals). The sample size was determined based on Krejcie and Morgan table and 181 employees were randomly selected via stratified sampling method. The instruments comprised the Job Diagnostic Survey (Hackman & Oldham, 1976), Organizational Justice Scale (Colquitt, 2001), and Organizational Commitment Questionnaire (Allen & Meyer, 1990). The face validity of the questionnaires was confirmed by experts. The obtained alpha coefficients for the reliability of the questionnaires were 0.76, 0.83, and 0.79, respectively. For the purpose of data analysis, descriptive and inferential statistics (Pearson correlation and multivariate regression) were utilized. The results demonstrated that there was a significant, positive relationship between job characteristics and employees’ organizational commitment. Furthermore, there was a significant, positive relationship between organizational justice and organizational commitment of the staff. According to the results of regression analysis, each of the components of job characteristics and perceived organizational justice had a different predictive power for organizational commitment of the employees.