Primary brain tumors were diagnosed in two aged, free-ranging cow elk (Cervus canadensis) in Colorado. Both animals had been observed prior to their deaths in an incoordinate, emaciated state and were apparently blind. At necropsy, a large astrocytoma involving primarily the left pyriform lobe was found in one animal and a meningeal sarcoma involving the optic chiasma and adjacent ventral meningeal surface of the brain was noted in the other elk.