The current basic goals in glioma surgery are radical tumor resection without triggering the development of new neurological deficits. Although complete removal of malignant gliomas is extremely difficult because of the tumors' infiltrative characteristics, gross total resection of the tumor is known to be associated with improved outcome in the patients. To enable safe and radical resection of malignant gliomas, especially those adjacent to eloquent brain areas, rapid progress has been made in the development of operative support techniques; e.g., navigation systems to provide information about the anatomical and functional locations in the brain and a fluorescence imaging technique for differentiating brain tumors from normal brain tissue. These intraoperative imaging techniques in glioma surgery have improved the functional outcomes of glioma patients.