Objective: The present study aimed to investigate the effects of group positive psychotherapy on increasing the happiness of mothers of children with cochlear implants. Methods:This study was a quasi-experimental research with pretest-posttest, a control group, and a 75-day follow-up design. A total of 20 mothers of children with cochlear implants treated in Baqiyatallah Hospital of Tehran City were randomly assigned to 2 groups (10 participants in the experimental and 10 participants in the control group). The experimental group received positive psychotherapy training during 10 sessions, 120 minutes in each session, one session per week and the control group received no interventions. Results:Research tool was Oxford Happiness Inventory, which was administered in 2 pretest and posttest steps and then the obtained data were analyzed using analysis of covariance method (ANCOVA). The results of ANCOVA showed that group positive psychotherapy was effective on happiness of mothers of children with cochlear implant (F 1, 17 =31.13, P<0.01). Conclusion:Group positive psychotherapy is an appropriate treatment approach to increase the happiness of mothers of children with cochlear implant.