Brain CT was made in 720 patients with tumors of the central nervous system. The subtentorial site of the process was encountered in 50.4% of cases. The paper outlines the skialogic characteristics of tumors having varying structures: medulloblastomas, ependymomas, astrocytomas, angioreticulomas, truncal gliomas, metastases, epidermoids, neurinomas, meningiomas, chemodectomas, arteriovenous malformations. Difficulties in determining the histostructure of tumors on the basis of skialogic manifestations were noted. Anatomic and skialogic approaches which may assume the type of a neoplasmic process were outlined.