An ectopic liver is a rare congenital abnormality that is difficult to detect before surgery due to its small size. A 53-year-old man had liver cirrhosis and received regular surveillance. An ovoid mass on the surface of the gallbladder separated from the liver proper was found on computed tomography (CT). The mass had grown slowly over five years of surveillance. Upon further evaluation, the mass exhibited iso-signal intensity compared to liver on T2-weighted images, precontrast T1-weighted images, and the hepatobiliary phase of gadoxetic acid-enhanced magnetic resonance imaging (MRI). Surgical resection was performed, and the mass was diagnosed as an ectopic liver with normal liver parenchyma without cirrhotic changes. This case demonstrates that ectopic liver with normal liver tissue can develop in a patient with liver cirrhosis and can grow in the absence of a tumor. MRI with gadoxetic acid is useful to identify this condition correctly.