Background <p>As population aging accelerates, elder abuse has become a public health concern. Although caregiver burden is recognized as an important risk factor for elder abuse, the psychological mechanisms underlying this association among nursing home caregivers remain unclear. This study aims to investigate the relationships among caregiver burden, well-being, negative coping, and elder abuse tendency, with a specific focus on the mediating effects of well-being and negative coping and the moderating role of care recipient dependency.</p> Methods <p>A cross-sectional study was conducted, recruiting 858 caregivers from 108 nursing homes from July to August 2025 in Fujian Province, China, using a convenience sampling method. Data were collected using the Zarit Burden Interview (ZBI), Caregiver Abuse Screen (CASE), World Health Organization Five Well-Being Index (WHO-5), and the negative coping subscale of the Simplified Coping Style Questionnaire (SCSQ). Structural equation modeling (SEM) was used to test the parallel mediating effects of well-being and negative coping, and multi-group analysis was performed to examine the moderating role of care recipient dependency.</p> Results <p>Caregiver burden, well-being, negative coping, and elder abuse tendency were significantly correlated (all <i>p</i> &lt; 0.001). Caregiver burden and negative coping were positive predictors of elder abuse tendency, whereas satisfaction with remuneration and well-being were negative predictors (all <i>p</i> &lt; 0.05). Well-being (<i>β</i> = 0.090, <i>p</i> = 0.008) and negative coping (<i>β</i> = 0.072, <i>p</i> = 0.012) significantly mediated the relationship between caregiver burden and elder abuse tendency. Multi-group analysis revealed that care recipient dependency significantly moderated the direct path between caregiver burden and elder abuse tendency (<i>Z</i> = − 2.889, <i>p</i> = 0.004): caregiver burden significantly positively predicted elder abuse tendency in the higher-dependency group (<i>β</i> = 0.288, <i>p</i> = 0.001), but not in the lower-dependency group (<i>β</i> = −0.091, <i>p</i> = 0.289).</p> Conclusion <p>Higher caregiver burden was associated with greater elder abuse tendency through pathways involving lower well-being and greater negative coping. Notably, a direct association between caregiver burden and elder abuse tendency was observed only among caregivers supporting higher-dependency older adults. These findings highlight the importance of strengthening caregivers’ psychological resources and coping capacities, and may inform targeted support and management strategies in institutional care settings.</p> Clinical trial number <p>Not applicable.</p>