The aim of this study was to investigate the relationship between self-esteem and stages of change among heroin users on methadone maintenance at the Maudsley Hospital. The sample was 31 male and female subjects. Subjects (mean age 33.5 yrs) were given a self-esteem questionnaire and stages of change questionnaire. These questionnaires have been classified to five stages, Precontemplation, Contemplation, Preparation, Action, Maintenance. Data was analysed by using Spearman correlation coefficient. Results show that there was a correlation between self-esteem and stages of change. This study suggests that this result would help us to assess heroin users at treatment.