Examination of cerebrospinal fluid (CSF) samples is important in postmortem examinations. CSF samples can be collected by performing lumbar or cisternal punctures. Additionally, if bloody fluid is aspirated during a spinal puncture, intracranial hemorrhage could be diagnosed. However, vascular injury and hemorrhage can occur during these procedures. The authors performed cisternal punctures during routine autopsies; further, to evaluate the usefulness of the former, the results were analyzed. Out of 50 cases, bloody fluid was aspirated in CSF samples of 20, while CSF samples of the other 30 were clear. Cases in which bloody fluid was aspirated were divided into blood-tinged and blood aspiration groups according to hemoglobin levels in the aspirated fluids. Cisternal punctures were characterized by high specificity and sensitivity; further, positive and negative predictive values were obtained that enabled detection of head and neck injuries including non-traumatic basal subarachnoid hemorrhage. Main head and neck injuries in blood aspiration group were skull base fracture, cervical fracture, and dislocation.