Background <p>Organizational commitment is emphasized as an essential element for improving nurses’ work performance and organizational productivity. There is a lack of research investigating both the direct and indirect factors influencing organizational commitment among long-term care (LTC) hospital nurses.</p> Purpose <p>This study explored the mediating effects of nurses’ professional values on the relationship between the nursing work environment and organizational commitment among LTC hospital nurses.</p> Methods <p>Participants included 154 nurses from nine LTC hospitals in South Korea. Data were collected using Korean versions of the Practice Environment Scale of the Nursing Work Index, Nursing Professional Values Scale-Revised, and Organizational Commitment Questionnaire. Subsequent analyses were conducted using Baron and Kenny’s three-step regression method and the Sobel test.</p> Results <p>The analyses showed that nursing professional values partially mediated the relationship between the nursing work environment and organizational commitment (Z = 3.43, <i>p</i> = .001).</p> Conclusion <p>LTC hospital managers need to make efforts to improve the nursing work environment and to promote nursing professional values for increasing nurses’ organizational commitment.</p>