Background & aim: The childbearing motivation is a global and complex process. It depends on several economic, political, social, and individual factors. Therefore, the present study aimed to investigate the correlation between personality traits and childbearing motivations of married women, considering the mediating role of psychological well-being.Methods: This was a correlational study designed to test a predictive conceptual model using structural equation modeling. The study population included all married women aged ۱۸ to ۴۵ in Hamedan, Iran, from the first April, ۲۰۲۳ to the end of September ۲۰۲۳, who were selected through a multi-site stratified sampling approach. Data were collected in person using the Childbearing Motivation Questionnaire, the Neuroticism-Extraversion-Openness Five-Factor Inventory, and the Scale of Psychological Well-being, with each session lasting ۲۰ to ۶۰ minutes. The final model was analyzed using Structural Equation Modeling and MIMIC analysis via SPSS and LISREL software.Results: Five personality traits and psychological well-being were significantly associated with both positive and negative childbearing motivations. The findings also indicated that psychological well-being was associated with the relationship between personality traits and childbearing motivations (P<۰.۰۱). Among the personality traits, neuroticism showed the strongest positive association with negative childbearing motivations (β=۰.۲۹۴) and the strongest negative association with positive childbearing motivations (β=-۰.۲۱۴). Extraversion showed the strongest negative association with negative childbearing motivations (β=-۰.۲۱۹), and conscientiousness showed the strongest positive association with positive childbearing motivations (β= ۰.۲۶۳). Conclusion: These findings clarify the associations between personality traits and individual childbearing motivations and provide preliminary implications for the development of interventions aimed at promoting psychological well-being.