An increasing number of immigrant students attend Italian schools, with the possibility of being involved in bullying episodes. A few studies have investigated this phenomenon, providing some evidence that immigrant students may face an increased risk of being bullied compared to native-born students. The present study adopted a mixed-method design, which may better detect the dynamics of bullying towards immigrant peers. Participants were 692 native-born and immigrant students (20.5% with immigrant background; 54.8% females) who filled in self-report measures about their bullying experiences, popularity, acceptance of diversity at school, and prejudice. Thirty-five pupils (54% with immigrant background) were also interviewed. Two hypothetical bullying scenarios were presented: one depicting a native-born victim and one depicting an immigrant victim. After each scenario, adolescents were encouraged to reason about the motives for bullying. Quantitative data showed that general bullying was associated with perceived popularity status among peers, while racial bullying was associated with prejudice but not peer status. The relevance of anti-immigrant prejudices in driving racial bullying emerged also from adolescents interviews. The qualitative data indicated that among the reasons for bullying, adolescents mentioned a desire for dominance and popularity, in particular when the victim was non-immigrant. Findings suggest that, in addition to individual and peer group-related risk factors, prejudice also needs to be addressed in anti-bullying interventions aimed to counteract racial bullying.