Background Nurses may experience organizational dehumanization, perceiving themselves as mere tools to achieve institutional goals rather than as valued healthcare professionals. Such perceptions not only harm their well‐being and work engagement but also threaten the quality and sustainability of healthcare delivery. While prior research has primarily focused on the negative consequences of organizational dehumanization, limited attention has been given to identifying effective organizational strategies to alleviate this issue. Drawing on self‐determination theory, this study explores whether, how, and when developmental human resource management (DHRM) practices can mitigate nurses’ organizational dehumanization. Methods We conducted a three‐wave time‐lagged study with 311 nurses across multiple hospitals. Hypotheses were tested using structural equation modeling. Results DHRM was positively related to nurses’ work meaningfulness, which in turn was negatively associated with organizational dehumanization. Work meaningfulness mediated the relationship between DHRM and dehumanization. In addition, mastery climate strengthened the positive effect of DHRM on work meaningfulness, thereby amplifying its indirect association with reduced dehumanization. Conclusions This study highlights the value of implementing comprehensive DHRM practices in healthcare settings to enhance nurses’ experience of meaningful work and alleviate organizational dehumanization. Additionally, fostering a mastery‐oriented climate within hospitals can further strengthen the positive influence of DHRM.