The aim of this research is to test the effectiveness of behavioristic group counseling using contingency contracting techniques in reducing bullying among Islamic boarding school teenagers. This research uses a single case experimental design experimental method with an AB design. The subjects in this research were ten students from class VIII . Data collection techniques used Islamic boarding school youth instruments. Data analysis using Wilcoxon Signed Ranks t Test . The results of statistical analysis using the Wilcoxon Signed Ranks t test showed differences in the intervention conditions compared to the baseline phase . Of the 10 experimental group respondents who were involved in the calculations, 10 people in line experienced a decrease from pretest to posttest. This is evidenced by subjects trying to reduce the frequency of carrying out bullying behavior . So it can be concluded that behavioristic group counseling using contingency contracting techniques is effective for reducing bullying among Islamic boarding school teenagers.