Background: Bullying remains a prevalent problem in educational settings, including Islamic boarding schools (pesantren), and has adverse effects on victims' psychological well-being, particularly by lowering their self-esteem. Students who experience bullying tend to develop irrational beliefs that lead them to feel worthless, inferior, and less confident in social interactions. This study aimed to examine the effect of Rational Emotive Behavior (REB) group counseling integrated with exemplary Islamic narratives on improving the self-esteem of santri who had experienced bullying. This study employed an experimental method using a Pre-Experimental One-Group Pretest–Posttest Design. The research participants consisted of six ninth-grade students from Tarbiyatul Mu’allimin Al-Islamiyah (TMI) Al-Amien Prenduan who had low to moderate levels of self-esteem and had experienced bullying. Data were collected using a self-esteem scale administered before and after the intervention. The treatment consisted of Rational Emotive Behavior (REB) group counseling integrated with exemplary Islamic narratives and was conducted over five sessions. Data were analyzed using the Wilcoxon Signed-Rank Test. The findings revealed that all participants showed an increase in self-esteem scores following the group counseling intervention. The Wilcoxon Signed-Rank Test yielded a Z value of -2.226 and a significance value (Sig. 2-tailed) of 0.026 (< 0.05). These results indicate a statistically significant difference between the pretest and posttest scores. The findings suggest that Rational Emotive Behavior (REB) group counseling integrated with exemplary Islamic narratives was effective in helping participants replace irrational beliefs with more rational ones, enhance their self-worth, and strengthen their self-confidence.