This study aimed to analyze the levels of personal aggression and victimization, ethnic-cultural aggression and victimization, self-esteem, empathy, social skills and gender in adolescents as potential predictors of bullying in Spain and Ecuador. The wide pluricultural sample comprised secondary education students from both countries (
N
= 25,190, average age = 13.92, SD = 1.306;
N
Spain
= 14,437;
N
Ecuador
= 10,753), who took part in the study by filling in a self-report. The results revealed that predictive models of bullying for both countries explain 50–70% of variance. A transnational predictive pattern of personal victimization can be observed based on the levels of ethnic-cultural victimization, ethnic-cultural aggression, personal aggression, self-deprecation, and affective empathy. A transnational predictive pattern of personal aggression is evidenced depending on the levels of ethnic-cultural aggression, personal victimization, self-deprecation, ethnic-cultural victimization, and the fact of being female. We concluded that bullying can largely be predicted by involvement in ethnic-cultural discrimination. These results are discussed, and educational inferences are drawn for prevention.