According to recent research, Korean women are very interested in calf reduction. Asian women want to have slim and straight legs more than Occidental women. Thick calves are divided by three types. One is muscular hypertrophy type and another is lipodystrophy type, and the other is mixed type. The authors focused on medial gastrocnemius muscle hypertrophy using radiofrequency generator. From July 2004 to July 2007, We did calf reductions for women who wanted to have aesthetically slim legs. Under intravenous anesthesia, we made a tiny pin hole with 18 gauze needle and injected local anesthetics. Radiofrequency probe(Dr. Oppel? radiofrequency, Sometech Medical Co.) was inserted and then We produced radiofrequency energy with a foot switch and made mean 150-200 points focal coagulation necrosis at each medial gastrocnemius muscle. There were little major complications such as seroma, hematoma, infection, gait disturbance, scar, sensory change etc. Some patients had moderate swelling during first week, but it was improved soon. Calf reduction using radiofrequency energy is very useful tool for hypertrophied medial gastrocnemius muscle. But we need more study for standardization of energy power, for certain amount of muscle damage to have reproducibility for predictability of durability and for possibility of rebound hypertrophy.