Non-invasive lipolysis procedures using highly-focused ultrasound (HIFU) became popular recently. This study evaluated therapeutic efficacy and adverse effects of HIFU lipolysis on body contouring in Korean patients. Baseline characteristics of patients were documented before treatment. Subjects were treated one time at the baseline using HIFU on their abdomen, thighs, or both. The circumferences were measured at the baseline, 1, 2, 3, and 12 months after the treatment. Adverse effects during and after the treatment were recorded at every visit. Twenty-six out of 50 subjects who were initially enrolled in the study completed 1, 2, and 3-month follow-ups, while 24 subjects completed 12-month follow-ups. A statistically significant circumference reduction was observed in the abdomen and/or thigh treatment group after 1 month and maintained for 12 months. Only seven subjects experienced slight circumference increase during the follow-up period. In conclusion, non-invasive HIFU lipolysis was effective for abdominal or thigh circumference reduction in Korean. Moreover, only one treatment session was enough to maintain a therapeutic effect for atleast 12 months.