OBJECTIVE To evaluate the benefits of the tumor thrombus types system on determining treatments and prognosis of hepatocellular carcinoma patients (HCC) with tumor thrombi in the portal vein. METHODS According to anatomic features of the portal vein in the liver and tumor thrombus of HCC developing modes, a uniform tumor thrombus types system (types I-IV) was first recommended. 84 HCC patients with portal vein tumor thrombi, which from January 2000 to January 2003 in the Eastern Hepatobiliary Surgery Hospital, were divided into I-IV groups according to types I-IV of the tumor thrombus system. The median survival periods and effectiveness of surgical resection or non-resection for I-IV groups were retrospectively observed. RESULTS The median survival periods for patients of group I (n=17), II (n=26), III (n=35) and group IV (n=6) were 10.1, 7.2, 5.7 and 3.0 months, respectively (p = 0.0001). From tumor thrombus type I to type III, the patients received surgical resection were better than that of non-resection (P = 0.0006). Among the patients receiving resection treatment, resection of tumor thrombus type I had the best effects, while for patients with tumor thrombus type IV, the results were not good. In case of non-resection treatments, the survival periods of patients with tumor thrombi type I, II and III were similar, which supposed that TACE may be of little effects on tumor thrombi. CONCLUSIONS Types of tumor thrombus system suggested may be helpful to determine the treatments and prognosis of HCC patients with tumor thrombi in the portal vein.