IntroductionPeer victimization is prevalent and associated with adverse outcomes. In this prospective study of youth who self‐reported interpersonal problems, we examined school connectedness, school behavioral difficulties, academic difficulties, and internalizing problems (social anxiety, self‐esteem, depression) as predictors of peer victimization and bullying perpetration severity. We also examined the moderating effects of gender.MethodsParticipants were 218 youth (66.5% female), ages 12–15 years (M = 13.5, SD = 1.1), who screened positive for peer victimization, bullying perpetration, and/or low social connectedness using self‐report measures. Youth were recruited from an emergency department in the United States as part of an intervention trial. Youth identified primarily as African American (53.7%) and Caucasian (31.7%). Youth completed a 6‐month follow‐up assessment (75% retention). Separate Bayesian regression models were used to examine the effects of baseline school connectedness, school behavioral difficulties, academic difficulties, and internalizing problems on the severity of 6‐month peer victimization and bullying perpetration.ResultsBaseline depression was positively related to both peer victimization and bullying perpetration severity. Baseline behavioral problems were positively related to bullying perpetration severity. Interactions indicated that gender moderated the relationship between school connectedness and peer victimization.ConclusionsGiven the adverse outcomes linked with peer victimization and bullying perpetration, an improved understanding of factors that predict victimization and perpetration severity may be helpful in defining intervention targets.