The present research aims to determine the effectiveness of spiritual intelligence training on coping with stress and self-actualization in adolescent girls. The research had a semi-experimental, pre-test, post-test and follow-up design. The statistical population consisted of all eighth-grade schoolgirls in the 12^th School District in Tehran in the school year of 2017-2018. Using multi-stage cluster sampling, 56 students were selected as the sample and divided into the experiment and control groups in random fashion. The spiritual intelligence package based on the educational protocols presented by Bowell (2004) was used. The questionnaire developed by Endler and Parker (1990) for coping with stress and the actualization questionnaire devised by Soleimani et al. (2015) were the tools used in this study. Data analysis was carried out by means of the SPSS software as well as descriptive statistical methods (mean and standard deviation) and inferential statistics (MANCOVA and the repeated measures ANOVA). The assumption that the variance-covariance matrices would be homogenous was tested using Box’s M test. Statistical analysis showed that 9 sessions of intervention through providing spiritual intelligence training led to a significant increase in problem-based coping strategies, positive emotions, relationships, finding meanings to life and progress in post-tests compared to pre-tests in the experimental group, while in the control group reduced emotion-based coping strategies and avoidance coping strategies were observed. Considering the positive effects of spiritual intelligence training, the findings of this research can be used in the planning of curriculum content on life skills so as to prevent social harms such as hazardous behaviors in adolescents.