Hepatic intracystic hemorrhage is a rare complication of polycystic liver diseases, such as autosomal dominant polycystic kidney disease (ADPKD). A hepatic cyst with mural nodules and septation may suggest the presence of a cystic malignancy, such as biliary cystadenocarcinoma. We herein report a case of hepatic intracystic hematoma with a mural nodule mimicking biliary cystadenocarcinoma in a patient with ADPKD. Hepatic intracystic hemorrhage with a mural nodule is a very rare occurrence. A fat-saturated T1-weighted magnetic resonance image may be useful for making an accurate diagnosis of intracystic hematoma.