The purpose of the present research, investigate the effectiveness of acceptance and commitment therapy on the fear of negative evaluation and quality of life in people with social anxiety disorder. The current research method was a semi-experimental type with a pre-test-post-test design with a control group. The statistical population of this research consisted of all people with a social anxiety disorder who is 1401, they had referred to the psychology clinics of Mahabad city. From among the statistical population, 20 people were selected as accessible sampling and were randomly divided into 2 groups of 10 people (control group and experimental group). Data collection was done by using of Jerabek Social Anxiety Scale, Brief Fear of Negative Evaluation Scale (BFNES), and Brief Quality of Life scale (QOL). The acceptance and commitment therapy protocol was implemented in 8 sessions of 90 minutes, once a week for the experimental group. Data were analyzed by SPSS-22 software. In addition to descriptive statistics, multivariate analysis of variance (MANOVA) was used to analyze the data. The findings obtained from the analysis of variance showed that there is a significant difference between the control and experimental groups in the post-test stage in reducing the fear of negative evaluation and increasing the quality of life. This research shows that acceptance and commitment therapy is useful for people with social anxiety disorder and can be used as a psychological intervention along with other interventions.