During the dissection of the cranial cavity of a 93-year-old male cadaver, two hard and irregular masses were incidental palpated in the parietal lateral lacunae of the superior sagittal sinus. Opening of both lacunae revealed two vascularized bony masses, which were firmly attached to the wall of the lacunae by fibrous bands. Each mass was found to have a gross appearance of cancellous bone with trabecular framework and multiple osseous canaliculi traversed by blood vessels. There were no observable pathological changes in the calvaria, other blood vessels and the brain in the vicinity of the lacunae. Such huge ossified masses can have mass effect on adjacent structures causing impaired venous blood flow and CSF absorption in the dural sinus with related complications and can also be important differential diagnoses for other intracranial clacifications or foreign bodies. Therefore, anatomists, pathologist, radiologist and neurosurgeons should be aware of such ossification in the dural sinuses.