This article examines how maltreatment experienced by adolescents is related to school engagement. Maltreatment includes physical, mental, and sexual violence along with sexual harassment, neglect, and witnessing domestic violence. School engagement refers to the students' relationship to all activities in the school. It describes students' thoughts, activities and participation as well as their emotions in relation to school. Analysis is based on the Finnish School Health Promotion data (N = 155,299) and analyzed by linear regression analysis. Results indicate that adolescents' maltreatment experiences are related to school engagement, regardless of gender, age, family structure, or immigrant background. Maltreatment increases functional engagement and decreases emotional and cognitive engagement. These results thus confirm that maltreatment can also cause immersion in schoolwork. The results can be used to prevent lower school engagement and maltreatment of adolescents.