This study examined (1) whether self-justifying bullying (i.e., moral disengagement) differs in hypothetical bullying situations of a newcomer peer depending on his or her immigrant status; and (2) whether the respondent's immigration status, age, gender, real life bullying participant role (as bully, assistant, reinforcer, defender, victim or outsider) and moral disengagement proneness moderate the differences in moral disengagement between non-immigrant vs. immigrant victims. Altogether, 342 ten-year olds (54% immigrants) and 292 twelve-year olds (45% immigrants) answered peer-report measures to assess participation in bullying and peer status, and self-report measures to assess moral disengagement proneness and situational moral disengagement related to vignettes in which the target of bullying was a non-immigrant vs an immigrant new classmate. For both non-immigrant and immigrant participants both types of moral disengagement were higher for non-immigrant than immigrant victims in the vignettes independent of the respondents' own immigration status. However, different participant bullying roles predicted the differences in moral disengagement between non-immigrant versus immigrant hypothetical victims among non-immigrant and immigrant students. Results suggest that, besides being a trait dimension, moral disengagement is also influenced by situational characteristics that need to be taken into account in order to prevent and tackle bullying effectively.