To prove the necessity and feasibility of portal vein embolization for the treatment of hepatocellular carcinoma (HCC), We observed the tumor vascularity and portal vein supply by vascular casting, Doppler pulse sonography and iodized oil embolization in 178 HCC noduls. Portal vascularity was found in 75.6% of noduls (34/45). In few noduls, which were smaller than 3cm in diameter, portal branches existed only without hepatic artery branches (7/35). Tumor portal blood supply was measured in 54.1% of noduls (59/109) by using Dopplar sonography. Portal tumor branch embolization was performed in 24 of patients with unreseatable HCC, all tumor noduls being filled with iodized oil. The combined portal vein and hepatic artery embolization was more effective than hepatic artery embolization in the control of the disease (P < 0.01).