Adolescents transitioning to high school may be at greater risk of depression and suicide if they are victims of bullying behavior. This study explored sex differences in bullying victimization (physical, verbal/social, and cyberbullying) and the impact on depressive symptoms and suicidal behaviors in ninth-grade students (N = 233). Females reported significantly more verbal/social and cyberbullying than male students. There were no significant sex differences in physical bullying; male students who reported physical bullying victimization were more likely to experience depressive symptoms. Verbal/social bullying predicted depressive symptoms in males and females. Females who reported being victims of cyberbullying were more likely to report depressive symptoms, suicide ideation, and suicide attempts. Eighteen students reported suicide attempts, and each also experienced verbal/social bullying. School nurses are positioned to reach out to transitioning students, screen for mental health issues, provide a safe place to talk about bullying experiences, and promote positive mental health.