Student-student relationships, as forms of peer interaction, are central components in school life and exert positive effects on children. Based on social cognitive theory, the current study examined the mediating effect of perceived discrimination on the association between student-student relationships and bullying victimization and the moderating effects of parental care and sex. A total of 2160 Chinese children aged 9-15 years (mean age = 12.04, SD = 0.88) completed the questionnaires regarding student-student relationships, bullying victimization, perceived discrimination, and parental care. After sex was controlled, student-student relationships were significantly and negatively associated with bullying victimization and this relation was partially mediated by perceived discrimination. Parental care moderated the association between student-student relationships and perceived discrimination as well as perceived discrimination and bullying victimization. Specifically, the negative relation between positive student-student relationships and perceived discrimination became stronger for children with a high level of parental care. The positive relation between perceived discrimination and bullying victimization became weaker for children with a high level of parental care. Compared to girls, boys who experience perceived discrimination are more likely to become victims of bullying. The present study contributes to our understanding of the key mechanisms underlying the association between student-student relationships and children's bullying victimization.