Objective: This study compared the impact of multiple exposures to potentially traumatic events (PTEs), including sexual victimization, physical victimization, and witnessed violence, on posttraumatic stress disorder (PTSD) and comorbid conditions (i.e., major depressive episode [MDE], and substance use [SUD]). Methods: Participants were a subsample of adolescents reporting at least one PTE (n=1,868) drawn from an epidemiological sample of adolescents in the US. Results: Findings revealed that multiple victimizations were more likely than a single incident exposure and experiencing multiple victimizations increased the risk for developing PTSD and comorbid disorders. Relationships existed between specific diagnoses and different types of victimization frequency. Multiple exposures to witnessing violence were associated with increased likelihood for any PTSD, non-comorbid PTSD, comorbid PTSD and SUD, and PTSD, SUD, and MDE. Multiple physical victimization incidents were associated with any PTSD and comorbid PTSD and MDE. Multiple sexual victimization incidents were associated with any PTSD, comorbid PTSD and SUD, and PTSD, SUD, and MDE. Conclusions: Multiple incidents of exposure to victimization increased the likelihood of developing PTSD and comorbid disorders over and beyond a single incident exposure. Practice implications: The study highlighted the importance of thorough assessment for multiple types of victimization incidents. Early intervention efforts should target risk reduction of revictimization among youth exposed to PTEs. (Contains 2 tables and 3 figures.)