OBJECTIVE: The aim of this study was to evaluate the prevalence of paraphilic thoughts/behaviors (including paraphilic disorders) with and without sexual addiction and sexual-related conditions in a sample of substance disorder patients. METHODS: This was a cross-sectional study of substance-dependent individuals who sought outpatient treatment in São Paulo, Brazil. Data included sociodemographic information, drug of choice, responses to questions about sexual behavior, and to the following standardized questionnaires: (a) Sexual Addiction Screening Test, and (b) Childhood Trauma Questionnaire. RESULTS: The sample comprised 134 persons who use drug, predominantly men (76.1%), 39.6% were aged between 18 and 29 years, and 54.9% were single. Most were persons who use polydrug, 73.9% were alcohol and cocaine users, 63.4% marijuana users, 81.1% tobacco users, and 5.2% steroid users. Prevalence of paraphilic thoughts/behaviors (including paraphilic disorders) with and without sexual addiction was 47%. The HPV/herpes and hepatitis B rates were 7.9% (P = 0.021) and 6.3% (P = 0.046) respectively. Paraphilic and nonparaphilic thoughts/behaviors were associated to the presence of childhood physical neglect (odds ratios [OR] = 4.7, 95% confidence interval [CI] 1.0 to 21.9), low educational level (OR = 7.2, 95% CI 1.4 to 36), heterosexuality (OR = 3.8, 95% CI 1.1 to 12.8) and youth (age 18 to 20 years) (OR = 5.6, 95% CI 1.4 to 11.8). CONCLUSIONS: The high prevalence of paraphilic thoughts/behaviors with or without sex addiction in persons who use drugs may be related to the experience of physical and emotional neglect during childhood and this possibility should routinely be investigated in clinical practice.