A case of pedunculated hepatoma which was preoperatively diagnosed as non-functioning adrenal tumor is reported. A 48-year-old man presented to our hospital for further examination of remittent fever and leg edema. Abdominal ultrasonography, computed tomographic scan and magnetic resonance imaging showed a right suprarenal mass, its continuity of liver was uncertain. Tumor vessels were visualized on selective right adrenal arteriography and right adrenal function and serum alpha-fetoprotein were normal. Preoperative diagnosis was non-functioning right adrenal tumor. On operation, the dissection between the tumor and the inferior part of liver was easy. Pathological diagnosis was hepatocellular carcinoma with sarcomatous change. Difficulty of preoperative diagnosis of pedunculated hepatoma is discussed.