Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 54 7 2025 07 08 1504 1515 Cong Hiep Duong Thai Nguyen University of Economics and Business Administration, Thai Nguyen, Vietnam Thuy Phuong Thi Do Thai Nguyen University of Economics and Business Administration, Thai Nguyen, Vietnam Trang Giang Thai Nguyen University of Economics and Business Administration, Thai Nguyen, Vietnam Kim Thoa Hoang C Hospital, Thai Nguyen, Vietnam 2024 10 21 2025 04 21 Background: Post-COVID-19 pandemic showed a marked increase in nurse resignations, which has exacerbated pressure on healthcare systems globally. Mental health and Perceived Organizational Support have emerged as critical factors influencing nurses' commitment to their organizations in the post-pandemic era. We aimed to explore the complex relationships between psychological well-being, work engagement, organizational commitment, and perceived organizational support within the Vietnamese healthcare context. Methods: The research employed a cross-sectional quantitative approach. The questionnaire was distributed through Google Forms during March and April 2024, providing valuable insights into the studied phenomena within Vietnam's unique socio-cultural landscape. Convenience and snowball sampling were used to gather data. Upon completion of data collection, a total of 302 valid observations were obtained. The analysis was conducted using PLS-SEM. Results: Work Engagement mediates the Psychological Well-being - Organizational Commitment relationship; Perceived Organizational Support moderates the Psychological Well-being - Organizational Commitment relationship; Perceived Organizational Support also moderates the mediation of Work Engagement between Psychological Well-being and Organizational Commitment. This study enhances the understanding of how Psychological Well-being and Work Engagement influence nurses’ Organizational Commitment and highlights the role of Perceived Organizational Support as a key organizational resource in shaping these mechanisms. Furthermore, Organizational Commitment is linked to demographic variables such as age and monthly income, with age being a positive predictor and monthly income a negative predictor. Conclusion: Healthcare managers can promote Nurses’ Organizational Commitment by employing strategies to enhance their Psychological Well-being, Work Engagement, and Perceived Organizational Support. https://ijph.tums.ac.ir/index.php/ijph/article/view/36985 https://ijph.tums.ac.ir/index.php/ijph/article/download/36985/8605