We evaluated the effect of renal dysfunction on the prognosis of hepatocellular carcinoma in 224 patients who underwent hepatic resection. Survival was compared between patients with (57 patients) and without renal dysfunction (116 patients), using a creatinine clearance </=70 ml/min as the cut-off value. There were no significant differences with respect to other preoperative characteristics, operative findings, or histology between the two groups. There was also no difference in survival between the two groups after hepatic resection. However, among 132 patients with a solitary tumor measuring </=5 cm in greatest dimension, the disease-free and overall survival rates of 36 patients with renal dysfunction were significantly worse after resection than those of the patients without renal dysfunction (p = 0.04 and p = 0.0003, respectively). By multivariate analysis, renal dysfunction was an independent factor indicating a poor prognosis for disease-free and overall survival after resection of small solitary tumors (p = 0.0401 and p = 0.0031, respectively). Renal dysfunction did not affect the overall prognosis after resection of hepatocellular carcinoma, but it worsened the prognosis of patients with small solitary lesions.