We encountered a case of small focal nodular hyperplasia (FNH) of the liver. It was difficult to distinguish FNH from hepatocellular carcinoma by means of sonography, computed tomography (CT), and angiography. After the injection of Lipiodol, it accumulated densely on FNH, but was washed away after a short time, as observed on the follow-up CT. This progress was different from that in hepatocellular carcinoma.