<p>This study aimed to examine the relationships among religious coping, loneliness, and self-stigmatization in caregivers of children with chronic illnesses. This study employed a cross-sectional and correlational design. The sample consisted of 500 caregivers of children receiving treatment for chronic illnesses at a private medical center between March 1 and July 10, 2025. The data were analyzed via hierarchical linear regression. Loneliness and religious coping explained 26% of the variance in self-stigmatization. A one-unit increase in negative religious coping led to a 0.815-unit increase in self-stigmatization (<i>p</i> &lt; 0.001). The effect of positive religious coping on self-stigmatization was not statistically significant (<i>p</i> = 0.113). Similarly, a one-unit increase in caregivers’ loneliness level resulted in a 1.372-unit increase in self-stigmatization (<i>p</i> &lt; 0.001). There was a significant positive relationship between loneliness and self-stigmatization, as well as between negative religious coping and self-stigmatization. These findings highlight the importance of implementing psychosocial interventions to reduce self-stigmatization in caregivers of children with chronic illnesses, particularly by addressing loneliness and negative religious coping.</p>