Hamartoma of the spleen is a rare benign lesion and the pathogenesis of this is not completely understood. It is usually incidentally discovered during an operation or autopsy. Since the first report in 1861 by Rokitansky, less than 150 cases of splenic hamartoma have been documented in the literature to date. The majority of the patients with this tumor are asymptomatic. However, a few of these lesions are associated with clinical features such as hypersplenism, cirrhosis of the liver and spontaneous splenic rupture. Because there are no specific symptoms, tumor markers or radiologic results, it is usually difficult to make a diagnosis before surgery and the specimen pathology. We report here on three cases of splenic hamartoma (a 33-year-old man associated with thrombocytopenia, a 29-year-old woman with a 6-month history of left upper quadrant abdominal pain and a 43-year-old man with synchronous hepatocellular carcinoma) and we review the relevant literature.