The study initially developed a hypothetical causal mechanism that links religiosity to control attitudes toward drug use. Opposition to drug use was represented by the dependent variable, control attitudes, i.e., attitudes toward the social control (formal or informal) of a behavior. In the proposed model, control attitudes were directly affected by two perceptive constructs: perceived self-harm and perceived immorality. The belief that drug use harms the user, is immoral, and must be controlled by formal and informal measures were all related to religiosity according to the hypothetical causal mechanism used in this study. To test this conceptual model, a mail questionnaire was administered to a random sample of the student population of a large State university in the Pacific Northwest in the spring of 1999. The questionnaire was sent to participants through the e-mail network of the university. A total of 276 students eventually returned completed questionnaires. The participants resembled the university student population in terms of age and academic status (undergraduate vs. graduate). Women were slightly overrepresented, and there was some evidence of overrepresentation of Asians and international students. For the purpose of the analysis, control attitudes, perceived self-harm, and perceived immorality were indexed by substance. This resulted in three variables (control attitudes, perceived self-harm, and perceived immorality) for each of the six substances (alcohol, cigarettes, cocaine, heroin, LSD, and marijuana). Religiosity was measured by beliefs in the existence of God, the devil, life after death, heaven, and hell. Religious individuals had a stronger tendency to perceive drug use as immoral; based on this perception, they were more likely to support social control measures to reduce it. This pattern held for all drugs used in the study. These findings confirm the importance of religiosity in shaping perceptions and attitudes toward deviance and social control. Understanding the religious basis and the moralistic component of normative culture will enable academics and policymakers to handle the issue of social control more effectively, conceptually, and practically. The identification of religious and moralistic elements in drug control attitudes should also cause social-control policymakers to question whether the official rationale for formal drug control policies should be justified on rational grounds unrelated to dependence on the religious attitudes of the public. 2 tables and 40 references