This study investigated how five core characteristics of a job affect creativity of employees. Previous studies called for investigating the mechanism through which job characteristics affect creativity of employees and also called for considering social facets of a job besides the core characteristics of the job. Addressing these calls along with utilising theoretical support, this study empirically investigated creative self-efficacy (CSE) as a mediating variable in the link between core job characteristics (CJC) and creativity of employees, and also investigated the supervisor support for creativity as a moderating variable in the mediated link between core job characteristics and employee creativity through creative self-efficacy. This study collected dyadic data from 252 employees and 61 direct supervisors of those employees, using questionnaires in the context of one of the Iranian major oil companies. Following the data analysis, the positive link between each of five CJC and CSE was found significant and the mediating role of CSE in the link between each of five CJC and employee creativity was supported, but no significant moderating effect of SSC in the mediated link between each CJC and employee creativity through CSE was found. In addition to the hypotheses of this study, the indirect, direct, and total effects of SSC on employee creativity through CSE were examined and found significant.