With this study I investigated the moderating effect of school climate on the relationship between adolescents’ school belonging and their delinquent behaviour. For this purpose, the relational survey method, 1 of the quantitative research methods, and the bio-ecological framework was used. The participants in the study were a total of 698 high school students, of whom 326 were female and 372 were male. The school belonging scale, delinquent behaviour scale, and school climate scale were used in the study. The IBM Statistical Package for the Social Sciences (SPSS) Amos version 25 program was used to analyse the quantitative data obtained. I applied correlation analysis and moderating analysis to determine the relationships between high school students’ perceptions of school climate, their school belonging, and their delinquent behaviour. According to the research results, a significant and negative relationship exists between students’ school belonging levels and delinquent behaviour. The results also show that school climate moderated the negative relationship between school belonging and delinquent behaviour. The school climate strengthens the significant negative relationship between school belonging and delinquent behaviour. Based on the findings, I suggest that educators should actively monitor and improve the psychosocial aspects of the school climate to increase students’ school belonging and reduce their delinquent behaviour.