Background and Objective: Since the social, individual and psychological effects of social anxiety could damage functioning of many children and teenagers, we decided to survey the effectiveness of cognitive-behavioral group therapy for social anxiety of female students. Materials and Methods: Method of this study was an experimental type. After performing social anxiety inventory, clinical interview based on DSM-IV-TR was conducted and 18 students (n = 9 for each group) were randomly selected in two groups experimental group (cognitive-behavioral group therapy) and control group (no treatment). After 12-session treatment (2 hours/session), social anxiety inventory was repeated as a post-test in both groups.  Results: The statistical t–test results showed that there were significant differences between the experimental and control groups regarding social anxiety with 99% confidence and with 95% confidence the clients could save the result of treatment until a month later.  Conclusion: Cognitive-behavioral group therapy must be effective on social anxiety in fifth-grade female students.