The purpose of this cross-sectional study was to investigate to what extent young adults with close ties to Mexico were at greater risk for self-reported negative mental health outcomes than comparison groups during drug-related armed conflict from 2008 through 2012, and the effect of type and number of traumatic events on mental health outcomes. Using the Harvard Trauma Questionnaire and the Hopkins Symptom Checklist, 202 university students living in the El Paso–Ciudad Juárez border region were surveyed for symptoms of depression, anxiety, and posttraumatic stress. Students with close ties to Mexico reported symptoms of anxiety and posttraumatic stress at significantly higher rates compared with those without connection to Mexico, but there was no significant difference in rates of depression. Although more than a third of participants reported experiencing 5 or more traumatic events connected with the drug war, being confined to home had the most significant effect. Frequency of traumatic events reported by students as well as rates of anxiety and posttraumatic stress symptoms were higher among students with greater connection to Mexico. Rates of clinically-significant depressive symptoms among all students were higher than expected for U.S. adults but comparable with all U.S. college students. This study presents important new data on the mental health effects of Mexico’s drug war.