Introduction: The purpose of this study was to investigate the relationship of work-family conflict (WFC) with overall health, workplace cognitive failure and marital satisfaction, considering the moderating role of sleep quality and work-family conflict self-efficacy.Method: Participants include 234 employees of the Aghajari Oil and Gas Production Company (AOGPC) who were selected by a stratified random sampling method. These participants completed the Work-Family Conflict Questionnaire, Pittsburgh Sleep Quality Index, Work-Family Conflict Self-Efficacy Questionnaire, Short form of Health Survey Questionnaire, Workplace Cognitive Failure Questionnaire, and the Marital Satisfaction Scale. Hierarchical regression analysis was used to test the hypotheses.Results: Findings indicated that WFC was negatively related to the overall health and marital satisfaction and was positively related to workplace cognitive failure. Results also revealed that sleep quality and work-family conflict self-efficacy moderated the relationship of work-family conflict with overall health, workplace cognitive failure and marital satisfaction.Conclusion: WFC has been an important area of research in organizational behavior. However, there has been an absence of investigations examining the moderating role of sleep quality and work-family conflict self-efficacy. This study showed that sleep quality and work-family conflict self-efficacy provide employees with the resources needed for lower WFC. Therefore, from a practical point of view, the organizations need to find the necessity of designing effective intervention strategies targeted at improving sleep quality and work-family conflict self-efficacy with the aim of reducing WFC.