This surveillance study was conducted to verify the post-market safety and effectiveness of bevacizumab, which was approved in Japan in 2013 for the treatment of patients with newly diagnosed and or recurrent malignant glioma.This was a prospective, observational, multicenter post-marketing surveillance study. Patients with newly diagnosed or recurrent malignant glioma scheduled for bevacizumab treatment were enrolled. The incidence and severity of adverse drug reactions were calculated. The effectiveness of bevacizumab was assessed by the 1-year survival rate and the overall survival rate.The safety analysis set and the effectiveness analysis set each comprised 258 of the 268 enrolled patients: tumours were newly diagnosed in 80 patients (31%) and recurrent in 178 patients (68.9%). The incidence of grade ≥ 3 adverse drug reactions was 15.1%. Adverse drug reactions of special interest included 14 cerebral bleeding events and 11 infections. Of the 80 patients with newly diagnosed malignant glioma, 44 (55%) were alive throughout the 18-month observation period. The 1-year survival rate for patients with newly diagnosed glioblastoma was 78%. Median overall survival was not calculated, but 51.2% of patients were alive at the last date of observation of the last observed patient. In patients with recurrent glioblastoma, the 1-year survival rate was 38.9%, and the median overall survival was 10.2 months.The results suggest no new safety concerns, and the effectiveness might be similar to previously reported data in clinical trials. Therefore, bevacizumab is considered as one of the treatment options for patients with malignant glioma in real-world clinical practice.