Many of addicts in their addiction period have voluntarily referred to rehabilitation centers. Evidences don’t show that most of addicts are not able to quit addiction for the long term so that more than 75 percent of people who have treated, less than 6 months again relapse into drug abuse. In this study, survey- descriptive method has been used in order to analyze effective factors on addiction relapse. To do this, statistical sample of 300 persons have responded through researcher-made questionnaire. To analyze data, descriptive and inferential statistics have been used. According to research results, it was determined that factors such as impact of addicted friends, addiction reminding factors, contaminated life’s environment and inefficiency of psychotherapy sessions in addiction relapse have played role in addiction relapse. Also impact of these factors on age and gender of self-introduced addicts are similar (P= 0.000). To prevent addiction relapse, recommendations such as providing consultants for rehabilitation centers, more accurate monitoring of police over places of drug distribution, preventing from traffic of under-treatment addicts to former places of drug distribution, preventing from communication of under-treatment addict with addicted friends and more concentration on treatment plans in first 3months of addiction relapse, seem necessary.