This research was administered with the aim of comparing lay beliefs about symptoms, causes, and cures of addiction between self-referred addicts, NA members and non-addict males. For this purpose, 150 participants were randomly selected from self-referred male addicts referring to the Outpatient Cessation Centre of Addiction in Isfahan in May-June 2006. Also, 150 male members of NA, who managed to participate in the three months research period of the association, and 150 non-addict males in the same age and regional residence as the self referred addicts were selected using simple random sampling for comparison. Research instruments consisted of a demographic questionnaire and Furnhum and Thompson's (1996) Lay Beliefs Questionnaire. The reliability and validity of the Lay Beliefs Questionnaire were studied and verified. This questionnaire has three subscales: beliefs about symptoms, beliefs about causes of addiction, and beliefs regarding cures for addiction. Data were analyzed using the Manova and LSD posthoc test. Results showed significant differences among different groups as follows: in overall scores of symptoms of NA members and the non-addict group in the onset of addiction (from symptoms subscale); self-referred addicts and the NA group, non-addicts, and the NA group and, non-addicts with antisocial tendencies (another subscale of symptoms); self-referred addicts and the NA, and NA members and no addicts in symptoms and family conditions (another subscale of symptoms); self-referred addicts from the NA, non-addicts, and NA members from the non-addict group in immoral tendencies (another subscale of symptoms); among self-referred addicts and the NA, and non-addicts, and NA members from the no addict group. In causes of addiction subscale, Manova and LSD post-hoc test revealed significant differences among self-referred addicts, non-addicts, and NA members. In cures of addiction subscale, results of Manova and LSD post-hoc test showed a significant difference among self-referred addicts, NA members, and non-addicts.