This study investigated associations between ethnicity, ethnic diversity, and bullying among 739 pupils enrolled in their last year of primary school. Hypotheses derived from social misfit and inter-ethnic relations theories were tested using the multilevel p 2 model. Our key findings were: (1) inter- and intra-ethnic bullying are just as common in ethnically heterogeneous as in homogeneous classes; (2) pupils belonging to the Turkish and Moroccan minority groups bully significantly more than native Dutch (in particular according to victims); the chance to be victimized does not depend on the ethnic background of the pupil; (3) the prevalence of inter- and intra-ethnic bullying depends on the level of ethnic diversity in the class; inter-ethnic and intra-ethnic bullying increase with increasing levels of ethnic diversity.