This analysis of a large, nationally-representative epidemiologic sample indicates that relative to adults with current cannabis use disorders only, adults with co-occurring cannabis use disorders and nicotine dependence were significantly more likely to report several current psychiatric disorders and reported engaging in a significantly higher number of antisocial behaviors but did not differ in physical health correlates. Relative to adults with current nicotine dependence only, adults with co-occurring cannabis use disorders and nicotine dependence were significantly more likely to report several psychiatric disorders plus several psychosocial problems but did not differ in physical health correlates.