Background : Individuals with comorbid alcohol and drug use disorders are at particularly high risk for a variety of problems, including other psychiatric disorders. In general, patients with comorbid alcohol and drug dependence tend to have more severe dependence problems and often have poorer treatment outcomes than individuals with single disorders. For treatment-seeking pregnant women, psychiatric comorbidity can lead to relapse and premature treatment dropout, with adverse consequences to mother and infant. Methods: Psychopathology, as measured by the Minnesota Multiphasic Personality Inventory–Revised (MMPI-2), was examined in 170 pregnant women admitted to a comprehensive treatment program for cocaine or opiate dependence. Most were single (75%) and African American (80%), with a mean age of 29 years. Thirty-six met DSM-III-R criteria for both alcohol and drug dependence (alcohol positive), whereas 134 were drug dependent only (alcohol negative). Results: Alcohol-positive women had higher levels of psychopathology than alcohol-negative women, with higher scores on scales 2 (Depression), 4 (Psychopathic Deviance), 8 (Schizophrenia), and 0 (Social Introversion;p < 0.05). The mean MMPI-2 profile for alcohol-positive women was 2-4-8 (Depression-Psychopathic Deviance-Schizophrenia; all T-scores > 65), whereas alcohol-negative women had only a scale 4 increase. Conclusions: Results suggest that pregnant, drug-dependent women with comorbid alcohol dependence present for treatment with greater psychopathology and thus may require more intense interventions than pregnant, drug-dependent women without comorbid alcohol dependence. Alcohol use by pregnant women is particularly important to address in treatment, because alcohol is a known teratogen associated with mental retardation and behavioral problems.