Isolated splenic peliosis is an extremely rare condition characterized by the presence of multiple blood-filled cavities, occasionally resulting in non-traumatic splenic rupture with fatal bleeding. In our case, a 64-year-old man was brought by ambulance due to weakness and abdominal pain without nausea or febrility. On clinical examination, the patient was sensitive to palpation with significant tenderness over the abdomen but no associated features of peritonitis. He collapsed during the imaging examination and became unconscious and asystolic. Cardiopulmonary resuscitation was not successful. The patient died approximately within 2 hours of admission to the hospital. Postmortal examination showed 2800 ml of intraperitoneal blood with clots and a laceration of the lower pole of the spleen. Macroscopic examination of the spleen revealed huge nodular splenomegaly, measuring 21 cm x 19 cm x 5 cm, weighing 755 g. On the cut surfaces, multiple randomly distributed blood-filled cavities ranging from 0,5 to 2 cm in diameter were seen. At microscopic examination, the specimens showed multiple irregular haemorrhagic cyst-like lesions that were not lined by any epithelium or sinusoidal endothelium, consistent with the diagnosis of peliosis lienis. Although the condition is often clinically silent, the forensic pathological significance arises from the differential diagnosis of resultant intraperitoneal haemorrhage and sudden death, mimicking a violent death.