OBJECTIVE To describe associations of antisocial behavioral syndromes, including DSM-IV antisocial personality disorder (ASPD) and conduct disorder without progression to ASPD ("CD only"), and syndromal antisocial behavior in adulthood without CD before age 15 (AABS, not a codable DSM-IV disorder), with body mass index (BMI) status in the general US adult population. METHODS This report is based on the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (n = 43093; response rate, 81%). Respondents were classified according to whether they met criteria for ASPD, AABS, "CD only," or no antisocial syndrome, and on current BMI status based on self-reported height and weight. Associations of antisocial syndromes with BMI status were examined using multinomial logistic regression. RESULTS Among men, antisociality was not associated with BMI. Among women, ASPD was significantly associated with overweight and extreme obesity; AABS was associated with obesity and extreme obesity; and "CD only" was significantly associated with overweight, obesity, and extreme obesity. CONCLUSIONS Assessment of antisocial features appears warranted in overweight, obese, and extremely obese women, and assessment of BMI status appears indicated in antisocial women. Prevention and treatment guidelines for overweight and obesity may need revision to address comorbid antisociality, and interventions targeting antisociality may need to include attention to weight concerns.