We report a case of combined hepatocellular and cholangiocarcinoma showing tumor growth and invasion to the diaphragm during interferon-alpha (IFN-alpha) and 5-fluorouracil (5-FU) combined intra-arterial chemotherapy. A 63-year-old female was in hospital for treatment of hepatic tumor in left lobe with portal venous tumor thrombus. She was treated by IFN-alpha/5-FU chemotherapy, and the tumor was significantly reduced. For 28 months, the tumor was successfully treated by IFN-alpha/5-FU chemotherapy. But, thereafter the abdominal computed tomography showed the tumor re-growth and invasion to the diaphragm. Then the patient underwent the tumor resection. The histological findings were consistent with combined hepatocellular and cholangiocarcinoma. Immunohistological examination revealed a heterogeneous expression of IFN-alpha receptor 2. This case suggested that the growth of cancer cells without sensitivity to IFN-alpha/5-FU chemotherapy and the blood supply via the diaphragm led the relapse of IFN-alpha/5-FU chemotherapy.