Anatomical hepatectomy for small hepatocellular carcinomas (HCCs) is widely preferred but evidence concerning its benefits is inadequate. The aim of this study was to determine whether patient outcome is influenced by the method used to treat small single HCCs.An analysis was performed on 168 patients who underwent curative hepatectomy for a single HCC smaller than 5cm between Jan 1998 and Dec 2001 at Seoul National University Hospital. Ninety-nine of these patients underwent anatomic resection and 69 patients non-anatomic resection. Overall survival rates, disease-free survival rates, and prognostic factors for survival and recurrence were analyzed.The cumulative 1-, 3- and 5-year overall survival rates were 86.9%, 73.6% and 65.5% in the anatomic resection group, and 88.4%, 63.8% and 49.7%% in the non-anatomic resection group, respectively (P = 0.032). And, the cumulative 1-, 3- and 5-year disease-free survival rates were 77.8%, 58.6% and 54.4% in the anatomic resection group and 62.3%, 42.0% and 28.6% in the non-anatomic resection group, respectively (P = 0.003). Anatomic resection was confirmed to be an independent favorable factor of disease-free survival by multivariate analysis.Anatomic resection for single small HCCs is superior to non-anatomic resection.