Undifferentiated carcinoma of the liver is very rare. A 54-year-old man was admitted to our hospital for a detailed examination of multiple liver tumors. These tumors were high or low echoic on ultrasonography, but not enhanced by contrast medium in dynamic computed tomography. A fine-needle aspiration biopsy specimen of the tumor showed undifferentiated carcinoma. The serum level of neuron-specific enolase was high (357 ng/ml) and the immunohistochemical stain of the biopsy specimen was positive for synaptophysin. We diagnosed the patient as having undifferentiated carcinoma of the liver with neuroendocrine features. The patient was treated with combined systemic chemotherapy: etoposide 100 mg/m2/day for three days plus cisplatin 80 mg/m2/day on day one. He achieved a partial response, the duration of which was 7+ months. The serum neuron-specific enolase levels were decreased to the normal range after chemotherapy. Primary liver carcinoma with neuroendocrine features is extremely rare, but in a suspicious case it is important to measure the serum levels of neuroendocrine markers and make a histological confirmation, because chemotherapy may be effective for this disease.