Malignant gliomas represent about 70 % of all brain tumors. Despite advances in standard therapy consisting of surgery, radiation therapy and chemotherapy, gliomas remain an essentially fatal disease, with a median survival time of 10 to 12 months and a 2-year survival rate of 8 % to 12 %. Electro-hyperthermia applied either alone or in combination with chemo- and/or radio-therapy is an advanced hyperthermia technique that has been used as adjuvant treatment for patients with malignant glioma. We present the results of a retrospective study of 140 patients with different stages of malignant glioma, which were treated/followed from January 2000 to February 2005. The endpoint was the overall survival and the survival from the 1st electro-hyperthermia treatment. The overall median survival time for patients with mostly advanced malignant glioma who received adjuvant electro-hyperthermia in this study was 20.4 months. The median survival time from the first electro-hyperthermia treatment was 6.6 months. Electro-hyperthermia was safe and well tolerated. The presented results show the feasibility of the treatment and suggest a benefit of the electro-hyperthermia treatment for patients with advanced malignant glioma.