A 43-year-old male patient was diagnosed as having hepatocellular carcinoma with portal vein thrombosis and arterioportal shunts. Three-dimensional conformal radiation therapy (3DCRT) with high focal dose was given to the left portal venous area. Shrinkage of the tumour and thrombus, disappearance of the arterioportal shunts and restoration of the hepatopedal flow of the portal vein was noted 3 months after treatment. The patient received further transarterial embolisation and achieved successful tumour control. No serious complications were encountered. 3DCRT is technically feasible and effective to treat a small volume of liver tissue with a high dose of radiation in this advanced disease.