The present study investigated the influence of bullying involvement and teacher-student relationship on school engagement, through the analysis of an explanatory model. For this, 426 students (from 6th to 9th grades) from four public schools located in a city in the state of São Paulo, Brazil, answered the Escala de Violência Escolar – Versão Estudante (School Violence Scale – Student Version), the Escala de Relação Professor-Aluno (Teacher – Student Relationship Scale) and the School Engagement Scale. Results from a Path Analysis indicated that bullying involvement has a direct negative impact on school engagement, and that teacher-student relationship has a direct positive impact on school engagement. Moreover, teacher-student relationship may mediate the negative effects of bullying on school engagement. These data confirm the importance of positive social relationships in school for student engagement. However, the proposed model explains 32% of the variance of school engagement, indicating that other variables not investigated in this study may also be relevant.