An increasingly important concern for clinicians who care for patients with cancers is their psychological problems and quality of life. The present study examined the efficacy of supportive group psychotherapy (SGP) on anxiety, depression and overall quality of life in patients with lung cancer undergoing gamma knife surgery (GKS).160 patients with lung cancer undergoing GKS were randomly divided into SGP group (n = 82) and care as usual (CAU) group (n = 78). Patients in SGP group received 90 minutes' group psychotherapy intervention once a week for 8 weeks, while patients in CAU group received usual care. Outcome measures were administered before and after the intervention and at 3-months follow-up. The primary outcome measures were the 14-item Hospital Anxiety and Depression Scale (HADS) and the secondary outcome measures were the 30-item European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30).Demographic characteristics between SGP and CAU groups showed no difference in sex, age, course of disease, years of education, marital status and profession. Psychological characteristics evaluated by HADS revealed that levels of both depression and anxiety in SGP group were significantly improved compared with that in CAU group at the end of the treatment and the improvement remained at the 3-months follow-up. In addition, EORTC QLQ-C30 demonstrated that functional scales including emotion, cognition and society in SGP group were significantly higher than that in CAU group at the end of the treatment and maintained till 3-months follow-up. EORTC QLQ-C30 also showed that symptom scales including fatigue, nausea/vomiting, pain, syspnea, insomnia, loss of appetite and financial problems in the former group were significantly lower than that in the latter group and maintained till 3-months follow-up. Furthermore, compared with that in SGP group before treatment, these variables in both HADS and EORTC QLQ-C30 showed obvious improvement in the same group after treatment and at the 3-months follow-up.The results suggested that SGP can alleviate anxiety and depression in patients with lung cancer following GKS and improve the overall quality of life.