Background: Nurses’ work engagement is essential both for the quality of the service provided and occupational health. However, there is a lack of adequate information about nurses’ engagement in healthcare organizations that are affected by various factors in the context of Health Psychology.Purpose: This study was aimed at investigating the association between leadership styles of supervisors and work engagement, and elucidating the role of organizational support in this relationship.Methods: A cross-sectional study was conducted on 85 nurses from the health organizations in Catalonia, Spain, recruited via a snowball procedure. Leadership styles and Three Outcome Scales (TOS) were evaluated through the Multifactorial Leadership Questionnaire (MLQ) as independent variables. POS as an Organizational Support Test assessed a mediating variable (POS), and work engagement as a dependent variable was evaluated by the Utrecht Job Involvement Scale (UWES).Results: The results displayed differences in work engagement depending on job positions. Besides, the results revealed a positive association between leadership styles and TOS with work engagement, other than laissez-faire. Additionally, POS illustrated a positive association with work engagement (r=0.447, p<0.01). Leadership styles except for laissez-faire and TOS positively affect POS; also, TOS significantly predicted work engagement (β=0.581, t(78)=2.196, p<.05). Furthermore, results confirmed that POS mediates the relationship between leadership styles and TOS with work engagement (z=-3.490; z=3.117; z=3.521; z=3.791, p=0.000).Conclusion: Transformational and transactional leadership are two main styles significantly affecting nurses’ engagement with their work, while laissez-faire decreases nurses’ work engagement; therefore, supervisors and leaders of healthcare organizations should consider it. Consequently, nurses with a high POS show superior engagement levels at work. The research sheds new light on health psychology and the clinical area, particularly in nurses’ work engagement.