The aim of this study was to assess the usefulness of postmortem contrast-enhanced CT (PMeCT) performed via direct large-vessel puncture when routine postmortem CT suggests a vascular lesion as the cause of death. PMeCT was performed in 9 cases (4 male, 5 female) with a mean age of 76 years (range 52–92) at the time of death. The mean time elapsed since death was 29.1 h (12.0–72.0). The location of the target vessel for puncture was determined based on the CT table position and a grid placed on the body surface. An 18-G spinal needle was advanced to the puncture site, and the needle tip was confirmed to have reached the intended blood vessel. Using negative pressure with a 20-ml syringe, the needle tip was advanced until reverse bleeding was confirmed. Diluted contrast medium was injected slowly to ensure its dispersion within the blood vessels. Following confirmation of no extravasation, additional doses of diluted contrast agent were injected in 3–4 divided doses, with CT scans obtained at each step to track the distribution of contrast agent over time. PMeCT was successful in all cases, revealing cardiac tamponade in 7 (ascending aortic dissection, n = 6; cardiac rupture, n = 1), thoracic aortic aneurysm rupture, n = 1, and iliac artery aneurysm rupture, n = 1. There were no cases of procedure-related extravasation (pseudo-lesions). When postmortem CT reveals pericardial hematoma or bleeding in the thoracic or abdominal cavity, PMeCT can identify the source of bleeding.