The present research explores risk factors for, and longitudinal associations of, sexual harassment by peers during adolescence. Eight-hundred and seventy-two African American and European American adolescents (65.4% African American, 51.1% females) were assessed during the summer after the eighth grade (mean age=14.2 years) and then again in the 11th grade (mean age=17.1 years). At the first assessment, adolescents were asked about their experiences with sexual harassment, their psychological reactions to sexual harassment, and also about their peer relationships, perceived pubertal timing, problem behavior, and mental health. At the second assessment, adolescents reported on their problem behavior and mental health. In general, youth who associated with peers who were involved in problem behavior were at risk for victimization. Among females, those who perceived themselves to be experiencing early pubertal development were also at risk. Additionally, for some adolescents, sexual harassment predicted later adjustment difficulties.