Introduction: Nurses' vigor at work profoundly impacts the quality of patient care. However, the determinants of nurses' vigor remain underexplored in the current nursing literature, and the mechanism through which these determinants exert their effects remains unclear., Aim: This study aimed to elucidate the mediating role of psychological ownership in linking decent work to nurses' vigor at work., Methods: A two-wave, time-lagged study was conducted to collect data from 289 nurses working across three hospitals in Port Said, Egypt, between March and June 2023. Data were collected using the Decent Work Scale, the Psychological Ownership Scale, the Shirom-Melamed Vigor Measure, on an Introductory Information Form. Mediation testing was performed using structural equation modeling., Results: Decent work was significantly associated with psychological ownership and vigor at work. Psychological ownership partially mediated the relationship between decent work and nurses' vigor at work., Conclusion: Decent work practices are critical in fostering nurses' vigor while working, and psychological ownership plays a mediating role in this relationship., Clinical Relevance: Hospital administrators should value decent work practices, which could enhance psychological ownership, resulting in a potential improvement in nurses' vigor at work., (© 2024 Sigma Theta Tau International.)