Inherited thrombophilia is a risk factor for dural sinus thrombosis (DST). To our knowledge, this is the first description with autopsy findings of a patient with DST associated with heterozygous factor V Leiden and a short activated partial thromboplastin time (aPTT). A 51-year-old woman presented with a 3-day history of headache, nausea, right-sided weakness, and focal motor seizure; she died 3 days after admission. At autopsy, a gross examination showed hemorrhage of bilateral parietal lobes and left primary motor cortex, uncal and tonsillar herniation, and pulmonary embolus of the right upper lobe. A microscopic examination of the brain showed an organizing thrombus in the superior sagittal sinus, diffuse cerebral edema, and extensive venous congestion. Laboratory studies showed heterozygous factor V Leiden by polymerase chain reaction and a very short aPTT of 17 seconds (reference range, 22-30 seconds). The combination of a heterozygous factor V Leiden mutation and a short aPTT may have contributed to the fatal DST in this patient.