This study examined religious behaviors in 380 homeless individuals. We hypothesized that higher frequency of religious attendance is associated with lower rates of use of all substances, lower rates of drug and alcohol dependence, and lower psychological distress. Individuals attending religious ceremonies at least weekly ("frequent attendees") were compared to infrequent attendees. Participants also provided qualitative information about their faith. In univariate analyses, frequent attendees had significantly lower rates of alcohol, cocaine, and opioid use than infrequent attendees. They also had lower rates of alcohol and drug dependence, lifetime suicide attempts, and psychological distress, but these differences were not significant. In multivariate analyses, religious attendance remained significantly associated with alcohol use and opioid use. Researchers need to examine how spiritual and religious practices can be effectively incorporated as a part of substance abuse treatment.