Correlates of heavy substance use among a household-based sample of young gay and bisexual men (n=428) were identified and the odds ratio (OR) was calculated. A total of 13.6% reported frequent, heavy alcohol use and 43% reported polydrug use. Compared with men employed in professional occupations, men in service positions (OR=3.77) and sales positions (OR=2.51) were more likely to be heavy alcohol consumers. Frequent gay bar attendance and multiple sex partners were related to heavy alcohol use, as well as to polydrug use. Polydrug users were more likely to be HIV seropositive (OR=2.05) or of unknown HIV serostatus (OR=2.78). HIV serostatus was similarly related to frequent drug use. These correlates of heavier substance use among young gay and bisexual men could be used to identify and intervene early with members of this population who are at risk of substance misuse, as well as HIV/AIDS risk.