The main goal of this study is to analyze "Students' school engagement in terms of friendship and teacher behaviors." The population of the study is all students at 4th grade within the boundaries of Istanbul Metropolitan Municipality. The data of the study were gathered from 2066 students from 62 schools. "School Engagement Scale," "Peer Attachment Scale" and "Perceived Teacher Behaviors Scale" were used apart from an information form developed by the researcher. Multiple Regression Analysis, T-test and one-way analysis of variance were used to analyze the data. Results show that; "students' relationship with their friends predicts school engagement most." Female students have a higher level of school engagement. Students who do cultural and sports activities, those who get support from counseling service and those who do not have a problem with transportation have a higher level of school engagement. Students in crowded classrooms have a lower level of school engagement. It is reckoned that this study is significant in terms of presenting negative variables affecting students' engagement in school which has an important role in their personal and social lives and in terms of taking necessary precautions.