Outcomes of hepatocellular carcinoma (HCC) lesions >3.0 cm in size including Barcelona Clinic Liver Cancer (BCLC) stage B after radiofrequency ablation (RFA) with a single electrode remain unsatisfactory. This study aimed to investigate the outcomes of RFA with multiple electrodes (ME-RFA) for HCC tumors 3.1-7.0 cm in size and BCLC stage B. This retrospective study included 70 consecutive patients with 58 medium- (3.1-5.0 cm) and 17 large- (5.1-7.0 cm) sized HCCs after ME-RFA using a controller. Outcomes in terms of complete response, primary technique effectiveness, local tumor progression, and overall survival were investigated. After 1-4 applications of ME-RFA, the rates of complete response and PTE in medium-sized tumors were 79.3% and 91.4%, respectively, and in large tumors were 76.5% and 94.1%, respectively. Overall, the major complication rate was 5.7%. After a median 21-month follow-up period, both two- and three-year estimated overall survival rates were above 80%. There were no significant differences in overall survival and local tumor progression rates between medium- and large-size tumors and among BCLC stages A, B1 and B2. A complete response to ME-RFA was the only significant factor associated with improved survival (p=0.008). In conclusion, ME-RFA can effectively treat 3.1-7.0-cm sized HCCs with a comparable outcome between medium- and large-size tumors and among BCLA stages A to B2.