Subtance abuse abuse (Narcotics, Psychotropics, and other Addictive Substances) is carried out illegally and is a complex problem in Indonesia. Substance abuse can affect changes in a person's behavior which can be overcome with motivational interviewing (MI) interventions. This study aims to see the effect of the application of motivational interviewing (MI) on the stages of change in behavior in patients who are being rehabilitated by drugs. This research method uses case reports to evaluate nursing implementation using motivational interviewing to improve behavior change in substance abuse patients who are being rehabilitated with three evaluations during 15 days of meetings. The stages of change measurement tool used is the URICA questionnaire. The results of this study showed that the patient's URICA value on the first day was 11.2 (contemplation) which increased after being given a motivational interviewing intervention on the fifteenth day to 12.9 (action). There is an influence between the application of motivational interviewing on increasing stages of change in subtance abuse patients so that it is hoped that this motivational interviewing can be used in a structured way.