Hepatocellular carcinoma (HCC) with sarcomatoid change is a rare neoplasm of the liver, and recurrent therapies for HCC such as transcatheter arterial chemoembolization and percutaneous ablation therapy are presumed to promote sarcomatoid change. A 73-year-old man was admitted to our hospital diagnosed as having liver cancer originating from hepatitis C-related cirrhosis without any previous treatment for HCC. Ultrasonography showed that the tumor was hypoechoic, 3 cm in diameter, with unclear margins. Computed tomography demonstrated a low-density lesion with ring enhancement on delayed phase. Under a diagnosis of poorly differentiated HCC the patient underwent liver resection. Histologically, the tumor consisted of proliferation of spindle-shaped sarcomatoid carcinoma cells with unclear trabecular and pseudoglandular structures including a nodule of typical moderately differentiated HCC, which was observed to shift mutually in one region. Here, we report a case of sarcomatoid HCC with a review of the literature.