Goals: To evaluate the impact of age on the prognosis of patients with hepatocellular carcinoma (HCC) undergoing percutaneous radiofrequency ablation (RFA). Background: Whether age plays an important role in the outcomes of HCC after RFA remains controversial. Study: Two hundred fifty-eight consecutive treatment naive HCC patients who underwent RFA were enrolled. Patients aged ≤65 years (n= 100) were defined as the younger group and those aged >65 years (n= 158) were the elderly group. Their clinicopathologic features and prognosis were compared. Results: Younger patients had a higher male-to-female ratio, higher prevalence of hepatitis B virus, and smaller tumor size than elder patients. After median follow-up of 28.5 ±18.7 months, 45 patients died. The cumulative 5-year survival rates were 81.3% and 65.4% in younger and elder HCC patients, respectively (P=0.008). Multivariate analysis disclosed that age >65 years, serum albumin level ≤3.7 g/dL, prothrombin time international normalized ratio >1.1, α-fetoprotein (AFP) >20 ng/mL, and no antiviral therapy after RFA were independent risk factors associated with poor overall survival. Besides, there were 163 patients with tumor recurrence after RFA. Multivariate analysis showed that age >65 years, platelet count ≤10 5/mm 3, AFP >20ng/mL, multinodularity, and tumor size >2cm were the independent risk factors predicting recurrence. Conclusions: Both liver functional reserve (serum albumin level, prothrombin time international normalized ratio, platelet count, and antiviral therapy) and tumor factors (tumor size, number, and AFP level) were crucial in determining post-RFA prognosis in HCC patients. Moreover, younger HCC patients have better overall survival and lower recurrence rate after RFA compared with elder patients.