Aim and Background: Today, substance use disorders and their serious consequences are associated with many serious medical and psychiatric problems. In this regard, the present study was conducted to compare the effectiveness of positivist psychotherapy and reality therapy on cognitive disorder and relapse anxiety in addicted patients. Methods and Materials: The research method was quasi-experimental with pre-test and post-test design and control group. The study population included all addicts undergoing treatment referred to specialized clinics for substance abuse treatment in Kerman in 2020. Among them, 45 (24 males and 21 females) were selected by the purposive sampling method and randomly assigned to three groups: 15 in the first experiment, 15 in the second experiment, and 15 in the control group. The first experimental group received a positivist psychotherapy intervention and the second experimental group received William Glasser reality therapy-each treatment-in 8 sessions of 90 minutes (2 sessions per week) as a group,The control group was placed on a waiting list for two months to receive the most effective intervention. In order to collect data, Mason et al. 's (1994) Cognitive Disorder and Anxiety Return Questionnaire was used to collect data. Fisher's analysis of covariance and post hoc tests were used to analyze the data. Findings: Findings showed that both positivist psychotherapy and reality therapy are effective in reducing cognitive disturbance and relapse anxiety in addicts,However, there was a significant difference between the effectiveness of these two treatments on reducing cognitive disturbance and relapse anxiety (P<0. 001). Conclusions: Based on the findings of the study, it can be concluded that positivist psychotherapy is more effective than reality therapy on cognitive disturbance and return anxiety to the addicts under treatment. Tarab returned to the addicts under treatment.