Hepatocellular carcinoma (HCC) is usually associated with varying degrees of cirrhosis. Among cirrhotic patients with solitary HCC in the absence of macro-vascular invasion, whether tumor size drives prognosis or not after hepatectomy remains unknown. This study aimed to investigate the prognostic impact of tumor size on long-term outcomes after hepatectomy for solitary HCC patients with cirrhosis and without macrovascular invasion. A total of 813 cirrhotic patients who underwent curative hepatectomy for solitary HCC and without macrovascular invasion between 2001 and 2014 were retrospectively studied. We set 5 cm as the tumor cut-off value. Propensity score matching (PSM) was performed to minimize the influence of potential confounders including cirrhotic severity that was histologically assessed according to the Laennec staging system. Recurrence-free survival (RFS) and overall survival (OS) were compared between the two groups before and after PSM. Overall, 464 patients had tumor size <= 5 cm, and 349 had tumor size > 5 cm. The 5-year RFS and OS rates were 38.3% and 61.5% in the <= 5 cm group, compared with 25.1% and 59.9% in the > 5 cm group. Long-term survival outcomes were significantly worse as tumor size increased. Multivariate analysis indicated that tumor size > 5 cm was an independent risk factor for tumor recurrence and long-term survival. These results were further confirmed in the PSM cohort of 235 pairs of patients. In cirrhotic patients with solitary HCC and without macrovascular invasion, tumor size may significantly affect the prognosis after curative hepatectomy.