Background and Objective: Parents of children with developmental disabilities, particularly autism spectrum disorders (ASDs), are at risk for high levels of distress. The aim of this study was to evaluate effectiveness of acceptance and commitment therapy on psychological flexibility and Health Promotion among mothers with autistic children. Methods: This study was a quasi-experimental pretest - posttest with control group. The study population was consisted of all mothers with autistic children in Qom city at 2017. Study sample consisted of 30 (15 for each group) mothers that were selected by as a voluntary and randomly recruits to each groups. Instruments for gathering data were WHO quality of life questionnaire and Acceptance and Action Questionnaire- II. Data was analyzed by SPSS v21 using Covariance analysis test. Results: Based on research findings, the acceptance and commitment therapy had significant impact on health promotion and psychological flexibility. Conclusion: According to the findings of the study, acceptance- and commitment-based therapy is an applicable treatment intervention for health and quality of life of mothers with autistic children.
