Cyberbullying is a phenomenon of growing social concern that affects an increasing number of children and adolescents from all the developed countries. Although there is a large body of literature on the relationships between school bullying and the family and school contexts, few studies have examined the influence of these social environments on the problem of cyberbullying. Using a quantitative methodology, the main objective of this study was to analyse the influence of the school and family contexts on victims of cyberbullying. The sample consisted of 1,062 Spanish adolescents (51.5% boys and 48.5% girls) from 11 to 18 years old (M=14.5; SD=1.62). Three comparison groups were formed: severe cyberbullying victims, moderate cyberbullying victims, and non-victims of cyberbullying. The results of the analysis of variance indicated that severe cyberbullying victims, compared to non-victims, scored significantly higher on family conflict and obtained lower scores on the remaining family (family self-concept, cohesion and expressiveness) and school (involvement, affiliation, and teacher support) variables considered in the study. Regression analyses revealed that academic and family self-concept and some dimensions of family and school climate predict cyber-victimization in adolescence. These novel results point to the importance of including the family and the school in cyberbullying prevention programs. PALABRAS CLAVE / KEYWORDS Ciberacoso, adolescencia, víctimas, Internet, teléfono móvil, escuela, familia, autoestima. Cyberbullying, adolescence, victims, Internet, mobile phone, school, family, self-esteem.