The study aimed to examine the correlation between teamwork in schools, administrative support perception, and sense of school belonging, and the mediating effect of teamwork on the correlation between administrative support and school belonging. The research was designed in the relational screening model, which is one of the quantitative research designs. 319 teachers working in elementary, middle, and high schools in Turgutlu/Manisa in Turkey in the 2018-2019 academic year participated in the study. In the study, the data was collected by using Teamwork, Administrative Support, and School Belonging Scale. In the study, it was determined that there were significant and positive correlations between teamwork, administrative support perception, and sense of school belonging. It was concluded in the study that the effect of teamwork on teachers' sense of school belonging was partially realized by administrative support.