It is well-established that childhood sexual abuse (CSA) increases risk for later substance abuse. However, less is known about the mechanisms by which CSA increases risk of substance abuse, including problem drinking. Research points to negative emotions as potential explanatory links between CSA and problem drinking, and suggests that pathways may differ for men and women. In the current study, we examined three potential mechanisms (anger, anxiety, and depression symptoms) by which CSA increases vulnerability for alcohol problems in a sample of youth receiving child welfare services (N = 301). Path analyses revealed that relations between CSA and problem drinking were partially mediated by anger symptoms in male adolescents. In female adolescents, links between CSA and problem drinking were fully mediated by anxiety and anger symptoms. These findings highlight similarities and differences in how CSA increases vulnerability for alcohol problems in male and female adolescents. Clinical and research implications are discussed.