Gliomatosis Cerebri (GC) is a rare tumor of the central nervous system. It is defined as a diffuse glial tumor that extensively infiltrates the brain, involving more than two lobes. And it is listed as a subtype of astrocytic tumors according to the newest 2007 (4th edition) WHO classification of tumors of the Central Nervous System. GC can be subdivided into Type Ⅰ and Type Ⅱ. Clinical findings for patients with GC are usually subtle and nonspecific. The lesions of GC generally show hypo, or isodensity on CT; a poorly defined diffuse hypo-or isointense signal on T1-weighted images, and a scattere ddiffuse hyperintense signal on T2-weighted images. Histological examination of GC reveals widespread infiltration of neoplastic glial cells with minimal destruction of pre-existing structures.Diagnosis of GC can be ascertained on the basis of a combination of clinical, radiological and pathological data. The treatment of GC includes radiotherapy and chemotherapy; however, the optimal therapeutic strategy is still not well established and prognosis of GC remains poor. This report reviews in detail the aspects of GC mentioned above, and three controversial issues are also discussed in the report.