Introduction: Musculoskeletal disorders are the most common occupational diseases and, to prevent these disorders, it is important to survey and recognition the significant factors underlying. This study has been made by tow object, the primary objective was to determine the prevalence of musculoskeletal disorders in the steel industry and, the conclusive goal was to examine the relationship between work-family conflict as social factors and musculoskeletal disorders.

Methods: This study was conducted in one of the country's steel industry in the steel sector with a research population of 270 workers. To study work-family conflict was used 18-item questionnaire Carlson and Kakmar that this questionnaire survey the six sub-scales of this type of conflict in two dimensions and, musculoskeletal disorders were assessed by using a Nordic questionnaire. In the end, the results were analyzed with SPSS 21.0 software.

Results: The mean score (SD) for the entire study population of work-family conflict is 50.30 (12.352). The relationship between work-family conflict and musculoskeletal disorders shows that work-family conflict in general and in the domains of time-based from work to family and family to work (P<0.001), strain-based only from work to family and behavior-based only from family to work shows a significant relationship with musculoskeletal disorders (P<0.05).

Conclusion: This study introduces new operating causes of musculoskeletal disorders and, states that the management of such conflicts can be helpful in reducing musculoskeletal disorders.