Tentorial subdural hemorrhage with its supratentorial and infratentorial extensions were diagnosed by cranial ultrasonography and computed tomography in 9 term newborns. Vacuum extraction or forceps delivery was used in 6 patients. Abnormal neurologic manifestations developed after a period of normality in 8 patients. Increased intracranial pressure was the most common presentation. All patients had hemorrhage at the falcotentorial junction near the incisura; 5 also had hemorrhage around the tentorial leaflet. Posterior fossa retrocerebellar subdural hemorrhage developed in 5 patients and posterior interhemispheric subdural hemorrhage developed in 4. All 6 patients who received conservative treatment had normal neurodevelopmental outcomes. Of the other 3 patients upon whom suboccipital craniotomies were performed, only 1 had a normal outcome. Although it localized the tentorial subdural hemorrhage either at the incisura area or at the tentorial leaflet, ultrasonography failed to identify all patients with retrocerebellar or posterior interhemispheric subdural hemorrhage. Parturitional tentorial subdural hemorrhage may not be uncommon. Ultrasonography and computed tomography are complementary in the diagnosis. Surgical decompression of the posterior fossa subdural hematoma is necessary only in the presence of acute hydrocephalus or signs of brainstem compression.