Pineal parenchymal tumors (PPTs) in adults are rare, and knowledge regarding their optimal management and treatment outcome is limited. Stereotactic radiosurgery (SRS) could be an effective and safe treatment modality for PPTs. Pineal parenchymal tumor of intermediate differentiation in a 34-year-old woman (upper figures) and pineocytoma in a 44-year-old man (lower figures) are shown as illustrative cases. Post-SRS MR images (right figures) showed dramatic responses in comparison with pre-SRS MR images (left figures).