Introduction: Religiosity and spirituality (R/S) are protective factors for substance use disorders. Despite that, few studies have evaluated the impact of R/S on motivation and self-efficacy for abstinence, especially for crack-dependent patients. Objectives: To verify the association between R/S, self-efficacy and motivation for change among crack users undergoing treatment. Method: Quantitative study conducted with 50 patients from a CAPS AD III located in Porto Alegre from March to October 2018. Assessments include the Duke Religion Index (DUREL), the World Health Organization Quality of Life, Spirituality, Religiousness and Personal Beliefs instrument (WHOQOL-SRPB), the University of Rhode Island Change Assessment (URICA) and the Drug Abstinence Self-Efficacy Scale (DASE). Results: WHOQOL-SRPB (beta 0.519, p=0.00) and intrinsic religiosity (beta 0.475, p=0.00) were statistically significant correlated with drug abstinence self-efficacy, controlling for socio-demographics. Intrinsic religiosity (r=0.32, p=0.02), non-organizational religiosity (r=0.28, p=0.04), WHOQOL-SRPB (r=0.29, p=0.03) and WHOQOL-SRPB connect (r = 0.40, p = 0.00), meaning (r = 0.31, p = 0.02), spiritual strength (r = 0.41, p = 0.00), and faith (r = 0.32, p = 0.02) were associated with the longest time in abstinence in life. Conclusion: Results demonstrates that different aspects of R/S have a positive impact on the treatment of crack dependent patients.