Subarachnoid hemorrhage located in the supracerebellar cistern is an unusual complication of supratentorial neurosurgery. To the best of our knowledge, only 5 case reports have described the occurrence of this rare hemorrhage after burr hole surgery/drainage for the treatment of chronic subdural hematoma. We present the case of a patient with this rare postoperative complication of subarachnoid hemorrhage located in the supracerebellar cistern immediately after the burr hole evacuation of chronic subdural hematoma without continuous subdural drainage. A possible underlying mechanism is also discussed. Although the complication may be associated with significant morbidity and mortality, most cases follow a benign clinical course as observed in our case.