The purpose of this study was to investgate combined effects of L-carnitine supplementation and exercise on body composition, serum lipids and adiponectin in obese high school female students. Eighteen female students with 35% fat in body weight participated in the study. Students were randomly divided into the following three groups; exercise and L-carnitine supplementation group (ELG: n=5), exercise group (EG: n=6) and control group (CG: n=7), each with seven students. They underwent 10 weeks of exercise (50 min/day, 5 times/wk, 10 wk, RPE 11~16). ELG was given L-carnitine (1 g/day), EG and CG were given placebos. Before and after this period, body composition, serum lipids and adiponectin in plasma were measured. The results of the study in the three groups were as follows: Fat mass and %BF were significantly decreased in ELG. On the other hand, free fat mass was significantly increased in ELG, however, other groups showed no changes. Total cholesterol was significantly increased in the control group. High density lipoprotein cholesterol and low density lipoprotein cholesterol were not different in the three groups. Triglyceride was significantly decreased in ELG. Adiponectin was significantly increased in ELG. This study demonstrated that exercise and carnitine supplementation have a positive effect on fat mass, %BF, free fat mass and adiponetin. Thus, we can improve proper dietary and training programs for obese students.