The prognostic factors for solitary hepatocellular carcinomas with a maximum tumor diameter of a 3 cm were investigated in 59 of 23 1 patients who underwent curative hepatic resections at the Department of Surgery 11, Nagoya University Hospital between January 1981 and December 1991. The 3-and 5-year survival rates of these 59 patients were 61% and 41%, respectively. As prognostic factors, tumor maximum diameter, vascular invasion, capsule formation, cell differentiation, tumor localization, hepatic functional reserve, extent of hepatic resection, and macroscopic surgical margin were selected in this study. Of the patients with a tumor size > 1.5 cm, those who underwent major hepatic resections (hepatic lobectomy or segmentectomy) tended to have better survival than patients who received minor hepatic resections (hepatic subsegmentectomy or limited resection). Although most patients with a tumor size 1.5 cm underwent minor hepatic resections, they had a good survival rate. According to Cox's multivariate analysis, the extent of hepatic resection was significantly correlated with long-term prognosis of patients with a solitary hepatocellular carcinoma s 3 cm in diameter, but the macroscopic surgical margin was not. Cell differentiation, vascular invasion, capsule formation, and tumor localization were all correlated with the long survival. These results suggest that the selection of an adequate operative procedure is an important factor for the long-term prognosis of patients with small, solitary hepatocellular carcinomas.