objectiv: The present study aims to investigate the effect of self-efficiency training on runaway girls life quality in Isfahan city. Method: The study has a single-subject method with multiple baseline across participants. The participants was three Isfahan Behzisti center runaway girls which came into the experiment in a stepwise fashion and received 12 individual sessions of self-efficiency training. Afterwards, they were given follow up tests after 2 successive weeks of training. A life quality questionnaire of world healthcare organization was used as data collection method. The results of the data chart analysis based on descriptive statistics' and visual analysis. Results: Results indices revealed that the intervention has been effective on the three individuals (100% of PND for two individuals and 91% for the other one individual). Conclusion: The results of the present study were compatible with those of previously conducted ones indicating that the life quality of individuals increases along with the increase in self-efficiency. As a result, self-efficiency training in this study increased the life quality of runaway girls under study.