This study evaluated the prevalence and correlates of substance abuse histories in 341 consecutive admissions to gambling treatment programs. After controlling for gender, income, and site, gamblers with substance abuse treatment histories (SATH; 31%) had more severe problems than gamblers with no substance abuse treatment histories (NSATH) on the Gambling, Alcohol, Drug, Psychiatric, and Employment scales of the Addiction Severity Index. The SATH group had more years of gambling problems and gambled more days in the month prior to initiating gambling treatment. The SATH gamblers were also more likely to be receiving treatment for mental health problems and reported greater lifetime psychiatric distress than NSATH gamblers. These data suggest that pathological gamblers with substance abuse treatment histories may present more persistent and severe gambling dysfunction and psychiatric problems than those without such histories.