The clinical features, pathologic findings and treatment courses of eight adults with central nervous system small-cell neuronal tumors were reviewed. Five patients had central neurocytomas, two patients central nervous system neuroblastomas, and one patient a neurocytoma-like spinal cord tumor. The neurocytomas were intraventricular, moderately cellular tumors with bland nuclei and perinuclear halos. Patients with neurocytoma were treated with surgery, radiation therapy, and/or chemotherapy, and have followed favorable clinical courses. The neuroblastomas were intraparenchymal, hypercellular tumors with necrosis and frequent mitoses. Patients with neuroblastomas were treated with surgery, radiation therapy and chemotherapy, with some clinical response, but overall poor survival. One of the two patients developed extracranial metastasis. The spinal cord tumor had histologic features of neurocytoma, and responded well to biopsy and radiation therapy. The cases are compared with the varieties of small-celled neuronal tumors described in the literature, and pathologic, histogenetic and treatment implications are discussed.