Glioma is the most malignant tumor in the brain, the origin of glioma is still unknown. Recently some papers indicated that glioma may be developed from cerebral cavernous malformation (CCM). We describe a man with a right temporal lobe CCM, after gamma-knife radiotherapy, the patient developed a low-grade astrocytoma in the area of the preexistent CCM. This case, together with other reports, may indicated an oncogenetic properties of CCM, and we proposed that CCM may be a pre-glioma lesion.