Spontaneous rupture is a rare complication of splenic hamartoma. A review of the literature revealed only four such cases. To the best of our knowledge, this is the first report of spontaneous rupture of splenic hamartoma associated with liver cirrhosis and portal hypertension. A 53-year-old woman, who was followed up for aortic dissection and hepatitis C virus (HCV)-related liver cirrhosis, was referred with sudden left chest and shoulder pain. An abdominal ultrasound showed intraabdominal bleeding, and computed tomography indicated rupture of a splenic tumor. Emergent splenectomy was carried out. The postoperative course was uneventful, and the patient was discharged on the 13th postoperative day. Pathology revealed the tumor to be a ruptured splenic hamartoma. The non-tumorous splenic parenchyma revealed congestive changes. We consider that the presence of liver cirrhosis and portal hypertension are risk factors for spontaneous rupture of the splenic hamartoma.