AIM: To evaluate the factors affecting the early tumor recurrence within one year in cirrhotic patients having a single small hepatocellular carcinoma (HCC) after complete tumor necrosis by radiofrequency ablation (RFA) therapy. METHODS: Thirty patients with a single small HCC received RFA therapy by a RFA 2000 generator with LeVeen needle. Tri-phase computerized tomogram was followed every 2 to 3 mo after RFA. The clinical effects and tumor recurrence were recorded. RESULTS: The initial complete tumor necrosis rate was 86.7%. Twenty-two patients were followed for more than one year. The local and overall recurrence rates were 13.6% and 36.4%, 33.3% and 56.2%, 46.6% and 56.2% at 12, 24 and 30 mo, respectively. No major complication or procedure-related mortality was found. The risk factors for early local tumor recurrence within one year were larger tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging. The age of patients with new tumor formation within one year was relatively younger (55.1±8.3 vs 66.7±10.8, P= 0.029). CONCLUSION: Large tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging are the risk factors for early local tumor recurrence within one year, and young age is the positive predictor for new tumor formation within one year. METHODS: Thirty patients with a single small HCC received RFA therapy by a RFA 2000 generator with LeVeen needle. Tri-phase computerized tomogram was followed every 2 to 3 months after RFA. The clinical effects and tumor recurrence were recorded. RESULTS: The initial complete tumor necrosis rate was 86.7%. Twenty-two patients were followed by more than one year. The local and overall recurrence rates were 13.6% and 36.4%, 33.3% and 56.2%, 46.6% and 56.2% at 12, 24 and 30 months, respectively. No major complication or procedure-related mortality was found. The risk factors for early local tumor recurrence within one year were larger tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging. The age of patients with new tumor formation within one year was relatively younger (55.1 ± 8.3 vs 66.7 ± 10.8, P = 0.029). CONCLUSION: Large tumor size, poor pathologic differentiation of tumor cells and advanced tumor staging are the risk factors for early local tumor recurrence within one year, and young age is the positive predictor for new tumor formation within one year.