Adolescents with alcohol use disorders (AUDs) often have major depressive disorder (MDD). While physical abuse and sexual abuse (PS Abuse) have been observed to be common in adolescents with AUDs, the influence of PS Abuse on comorbid MDD and AUD has not been determined. The effect of pre-existing PS Abuse on the young adulthood outcomes of adolescents with AUDs has also not been adequately explored. This study examined the relationships among PS Abuse, MDD, and AUD in adolescence, as well as related young adult outcomes. Adolescents (mean age: 16.4 years; range: 14-18 years) were recruited from clinical and community sources and classified into four groups: (1) AUD+PS Abuse (n=154), (2) AUD only (n=255), (3) PS Abuse only (n=74), and (4) Controls (n=268). Subjects were longitudinally assessed through young adulthood (age 19 years or older). Measures included interview assessments of DSM-IV AUD and MDD, classified as "primary" or "secondary", and questionnaire measures of alcohol consumption and depression. Primary MDD preceded AUD whereas secondary MDD had a later onset than AUD. PS Abuse accelerated the onsets of primary MDD, secondary MDD and AUD. While affected adolescents had typically improved in both alcohol consumption and depression at the young adult assessment, the majority of those with adolescent AUD had AUDs in young adulthood, and MDD remained common in those with a history of PS Abuse. These results indicate that MDD among adolescents with AUD may be partly attributable to PS Abuse.