Objective: the present study aimed at studying the relationship between job stress and personality traits and also if the effect of job stress on personality traits was moderated by social support. Method: The populations consisted of offshore personnel working in Iranian Offshore Oil Company (IOOC) in Kharg Island. 234 participants using convenience sampling answered three questionnaires (job stress, very brief NEO-form, and perceived social support of family-scale). Four main hypotheses using structural equation analysis were examined. Results: The findings showed a predictive effect between the personality traits and job stress except for openness to experience such that job stress had an increasing effect on neuroticism and a decreasing effect on extraversion, agreeability, and conscientiousness. Social support, on the other hand, as a moderator decreased the effects of job stress on personality traits except for openness to experience, extraversion, and agreeability such that it decreased neuroticism and increased conscientiousness. Conclusion: the results generally revealed the predictive effects of job stress on personality traits and showed that social support, as a buffer, can reduce the effects of job stress on personality traits. The results were discussed based on the existing models on personality changes.
