One of recent social issues is that fitness in adolescence has been decreasing, while obesity has been rapidly on the rise. In addition, adolescent’s obesity, as well known, is closely linked to adult’s obesity. Therefore, the purpose of this study was to investigate the relationships between body mass index (BMI), VO?max, and cardiovascular disease risk score of Korean male adolescents and their parents’ BMI. Two hundred sixty four male adolescents participated in this study. Means and standard deviations of parents’ BMI, and adolescents’ body composition, VO?max, and cardiovascular disease risk score from blood analysis were calculated, and the correlation between parents’ BMI and adolescents’ variables was measured. In addition, after all of participants were classified into four groups based on their parents’ BMI, one-way ANOVA was conducted to compare groups, and Duncan as a post-hoc test was employed to compare differences among groups. Father's BMI was statistically correlated with their children's body weight, BMI, %body fat, waist circumference, hip circumference ratio, and VO?max, whereas mother's BMI was not. Additionally, all of participants were classified into four groups based on their parents’ BMI (that is, the standard of parents’ BMI is above or under 23㎏/㎡), and then group mean differences were compared. The four groups were categorized into Normal Weight Father & Mother group, Obese Father & Normal Weight Mother group, Normal Weight Father & Obese Mother group, and Obese Father & Mother group. There was a significant difference between weight, BMI, Body fat kg, body fat %, and VO?max of adolescents whose both parents were in lean weight and adolescents whose both parents were ≥23 in BMI. In addition, there was a significant difference between BMI, body fat %, waist, and hip of adolescents whose father reported ≥23 in BMI and mother reported <23 in BMI and adolescents whose both father and mother were >23 in BMI. The results of this study indicate that father’s BMI is a significant predictor of adolescents’ BMI and fitness, whereas mother’s BMI is relatively not.