Adolescents are at an increased risk for experiencing dating and relationship violence (DRV) and gender-based violence (GBV). School-based interventions remain an important and frequently used method for DRV/GBV prevention. A clear understanding and description of the different components of school-based interventions specific to DRV/GBV is needed to organize and advance the array of prevention efforts being utilized in school settings. We conducted an intervention component analysis to create a taxonomy for school-based interventions addressing DRV and GBV. We searched 21 databases in July 2020 and updated searches in June 2021, alongside extensive supplementary search methods. We included randomized controlled trials (RCTs) in adolescents of compulsory school-age that were implemented within the school setting which partially or wholly focused on DRV and GBV topics. Our analysis included 68 studies describing 76 different school-based interventions. Through an iterative coding process we identified 40 intervention components organized within 13 activity categories, including both student-directed components and non-student-directed components such as activities for school personnel and family members of students. We also identified components addressing higher levels of the social-ecological model including structural-social and structural-environmental aspects of DRV/GBV which prior reviews have not considered. This taxonomy of components and synthesis of intervention efficacy for DRV/GBV school-based interventions provides a framework for comparing past intervention evaluations and constructing new interventions to address these issues at multiple levels within a community.